Method and apparatus for magnetic transfer

ABSTRACT

A magnetic transfer wherein the exchange of master mediums is made easy to perform is provided, whereby the operational efficiency and transfer efficiency are improved, leading to an overall improvement in productivity in the manufacture of preformatted slave mediums. A master fixing base for determining and supporting the position of a master medium, which bears transfer data, and a conjoining apparatus for conjoining the master medium and the slave medium that is to receive the transfer therefrom are provided. The master medium is exchanged along with the master fixing base. It is preferable that a cleaning means be provided.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a magnetic transfer apparatus formagnetically transferring the data borne on a master medium to a slavemedium.

2. Description of the Related Art

A magnetic transfer method is a method comprising the steps of: bringinga master medium, on which a transfer pattern has been formed, into closecontact with a slave medium, which has been provided with a magneticrecording portion for receiving the transfer, to form a conjoined body;and applying a transfer magnetic field to the conjoined body so as totransfer and record the magnetic pattern corresponding to the transferdata (such as servo data) onto the slave medium.

This magnetic transfer method has been described in Japanese UnexaminedPatent Publication Nos. 63(1988)-183623, 10(1998)-40544, and10(1998)-269566, for example.

However, when performing magnetic transfers according to the magnetictransfer method described above, the surface of the master mediumbecomes littered with dust and other debris that becomes attachedthereto through the repeated usage thereof. This dust and debris canconsist of foreign matter originating in the surrounding environment,which becomes lodged between the master and slave medium, or materialoriginating from the master and/or slave medium, which is scraped fromeither surface thereof, respectively, when said master medium and saidslave medium are brought into close contact.

If a magnetic transfer is performed when there is dust or other debrisattached to the surface of the master medium, adequate contact betweenthe area of the surface of the master medium centering on the dust ordebris attached thereto and the surrounding vicinity thereof and thecorresponding area of the slave medium cannot be ensured; whereby apattern of a predetermined signal level cannot be transferred, and thetransfer quality becomes deteriorated thereby. For cases in which therecorded signal data is a servo signal, there is a problem in that anadequate tracking function cannot be obtained, and the reliability ofthe transfer is deteriorated thereby.

By repeatedly bringing a master medium, onto the surface of which dustand/or debris has become attached, into close contact with slavemediums, the attachment strength of the dust and/or debris to thesurface of the master medium is heightened; whereby deficiencies inpattern transfer of the same or greater magnitude are repeated duringthe performance of magnetic transferences to slave mediums subsequentlybrought into close contact with said master medium, and said dust and/ordebris becomes the cause of multiple faulty products. Further, thesurface of the master medium becomes deformed by this attached debris,and a problem arises in that the proper functionality thereof is lost.

Further, in this regard, cleaning technology, wherein a cleaning disk towhich a cleaning pad has been attached is pressed against the surface ofthe master medium to remove dust and debris that have become attachedthereto has been proposed as described in Japanese Unexamined PatentPublication No. 2000-285367, for example. Further, removal of attacheddust and debris by washing can also be considered.

Still further, for cases in which the slave medium is a disk shapedmedium such as a hard disk or a high-density flexible disk, a transfermagnetic field is applied to a conjoined body formed of a slave mediumand a master medium(s) brought into close contact with one or bothsurfaces of the slave medium, by use of a magnetic field generatingmeans employing an electromagnetic apparatus or a permanent magnetapparatus (es), which is disposed on one or both sides of the conjoinedbody. An important issue regarding the improvement of the transferencequality occurring in the magnetic transference relates to the bringinginto close contact the master medium and the slave medium so that thereis no gap whatsoever therebetween. That is to say, if there aredeficiencies in the contact between the respective surfaces of themaster medium(s) and the slave medium, regions on the slave medium ontowhich the magnetic transfer has not been effected occur; whereby thequality of the transferred and recorded signal is deteriorated due tothe occurrence of signal omissions in the magnetic data transferred tothe slave medium. For cases in which the recorded signal is a servosignal, a problem arises in that an adequate tracking function cannot beobtained, whereby the reliability of the magnetic transfer isdeteriorated.

Generally speaking, with regard to magnetic storage mediums, there is ademand for increased storage capacity and low cost. Further desired areso-called high-speed access mediums, which are capable of advantageouslyreading out the data of a desired location in a short time. Examples ofthese mediums include hard disks and HD (high-density) flexible disks;so-called tracking servo technology, wherein the magnetic headaccurately scans a narrow width track to achieve a high S/N ratio, playsa substantial role in attaining the high storage capacity thereof. Aservo signal, address data signal, replay clock signal, etc., used fortracking within a certain interval occurring in one rotation of the diskare “preformatted”, that is, recorded on the disk in advance.

The magnetic head is set so as to be capable of reading out thepreformatted signals and correcting its position thereby, whereby themagnetic head can accurately scan the track. According to the currentlyavailable preformatting technologies, one disk at a time, one track at atime is recorded by use of a specialized servo recording apparatus.

However, because the servo recording apparatuses are expensive and thepreformatting operation consumes a considerable amount of time, thisprocess accounts for a significant portion of the manufacturing costsincurred in producing preformatted disks; a reduction of said costs isdesirable.

Meanwhile, methods of utilizing magnetic transfer to achieve thisobjective, not writing one preformatting track at a time, have beenproposed. Magnetic transfer methods have been proposed in, for example,Japanese Unexamined Patent Publication Nos. 63(1988)-183623,10(1998)-40544, and 10(1998)-269566. According to these magnetictransfer technologies, because a master medium and a slave medium arebrought into close contact to form a conjoined body, and a transfermagnetic field is applied thereto, whereby a magnetic patterncorresponding to the data (e.g., a servo signal) borne on the mastermedium is transferred to the slave medium, the preformatting can beperformed without changing the relative positions of the master mediumand the slave medium—that is, while the two media remain stationary; notonly is it possible to perform an accurate recording of the preformatdata, it becomes possible to do so in an extremely short time.

Further, for cases in which the slave medium is a disk shaped mediumsuch as a hard disk or a high-density flexible disk, a transfer magneticfield is applied to a conjoined body formed of a slave medium and amaster medium(s) brought into close contact with one surface or bothsurfaces of the slave medium, by use of a magnetic field generatingmeans employing an electromagnetic apparatus or a permanent magnetapparatus(es), which is disposed on one or both sides of the conjoinedbody. When the transfer magnetic field is applied, in order to apply themagnetic transfer current in the track direction of the slave medium,the conjoined body, formed of the master medium(s) and the slave mediumthat have been brought into and maintained in close contact, or themagnetic field is rotated relative to each other, whereby a magneticpattern is transferred to the track on the entire circumference of thedisk shaped slave medium.

An important issue regarding the performance of this magnetic transferrelates to the accurate positioning of the slave medium and the mastermedium. In particular, regarding the slave medium, which is a hard diskor the like, the rotational center of the drive apparatus into which theslave medium is to be loaded after a magnetic pattern has beentransferred thereto must be accurately aligned with the center positionof the magnetic pattern that has been transferred and recorded onto saidslave medium. In this regard, it is difficult to manufacture the mastermedium so that the center of the pattern of the transfer data and thecenter position of the body of the master medium itself are accuratelyaligned; for example, there are cases in which even if a hole fordetermining the center position has been formed in the master medium,the accuracy of the process whereby said hole has been formed has beeninsufficient.

Regarding the points described above, an image apparatus wherein thepositions of the master medium and the slave medium are determined whensaid master and slave medium are brought into close contact is describedin Japanese Unexamined Patent Publication No. 11(1999)-175973. Morespecifically, after first setting the slave medium into a settingflange, a master medium, which is provided with a transparent portionhaving a marker corresponding to the transfer pattern is loaded thereon,and the position of the master medium is adjusted while the position ofthe marker and the position of the slave medium are observed by use ofan image apparatus, so as to be aligned, and then said master and slavemedium are brought into close contact.

Here, when the master medium is to be cleaned, the master medium isremoved from the magnetic transfer apparatus, and each type of dust anddebris attached to the surface thereof is removed; because the mastermedium must then be again loaded into the magnetic transfer apparatus, aproblem arises in that the operation rate of the transfer is reduced dueto the difficulty of properly positioning the master medium.

In particular, because the accuracy obtained by a simple positioning isinadequate due to the fact that the transfer pattern, such as a servopattern or the like, formed on the master medium becomes finer as therecording capacity thereof is increased, and the ability of thepredetermined functions thereof to be accurately performed cannot beensured if the center position of the transfer pattern and therotational center of the slave medium are not aligned with a high degreeof accuracy, a troublesome operation wherein the servo pattern or thelike must be observed by use of a measuring microscope or the like andaligned is required. Therefore, because time is consumed in removing andreloading the master medium, production inefficiencies arise.

Further, there is also a fear that airborne dust will become adhered tothe surface of the master medium or that dust adhering to the hands ofan operator or to components of the apparatus coming into contact withthe master medium will become transferred to the surface of the mastermedium when the master medium is being conveyed or loaded after thecleaning process has been performed thereon; thus causing deficienciesin the magnetic transfer.

The present invention has been developed in view of the foregoingproblems, and it is an objective of the present invention to provide amagnetic transfer apparatus wherein the exchange of the master mediumcan be performed easily, the transfer operation rate is improved, andmore efficient production is realized.

Further, according to current magnetic transfer apparatuses, in order toimprove the contact between the master medium and the slave medium, apressing means is employed for applying pressure to the master medium soas to press the slave medium against the master medium, and for removingthe air between the respective contact surfaces of the master and slavemediums by use of suction so as to reduce the quantity of air remainingtherebetween.

At this time, a lower chamber, in which the master medium is held inposition, and an upper chamber, in which the slave medium that is to bepressed against the master medium is held in position are provided;wherein the upper surface of the lower chamber and the lower surface ofthe upper chamber are provided with a sealing element such as an O-ringby which both of said surfaces are brought into close contact andhermetically sealed. In this configuration, if the degree of vacuumwithin the interior is increased, the sealing element deforms, thepressure increases, and the degree of vacuum and the contact pressurecannot each be controlled independently. Therefore, an optimal degree ofvacuum and an optimal contact pressure cannot be obtained, leading tocontact deficiencies, and causing a deterioration of the durability ofthe master medium.

That is to say, if the pressure exerted by the slave medium against themaster medium is increased, a problem arises in that the micro unevenpattern, which corresponds to the transfer data, formed on the mastermedium becomes more prone to being damaged, and the durability of thesurface thereof is also adversely affected. Further, if the degree ofvacuum is reduced, it becomes more likely that the quantity of airremaining between the contact surfaces will increase.

SUMMARY OF THE INVENTION

The present invention has been developed in view of the foregoingcircumstances, and it is an objective of the present invention toprovide a magnetic transfer apparatus wherein the degree of vacuum andthe conjoinment pressure occurring when the master medium and the slavemedium have been brought into close contact can be optimized, wherebythe contact property between the respective contact surfaces can beimproved and the magnetic transfer can be performed favorably.

Further, although technology has been proposed, as described in JapaneseUnexamined Patent Publication No. 7(1995)-78337, wherein an elastic bodyis used to press against the entirety of the back surface of the mastermedium under uniform pressure by a pressure contacting means in order toimprove the contact between the master medium and the slave medium,according to the application of this type of means as a solution,because the entire surface of the slave medium is pressed against by theelastic body, problems arise such as the overall pressure required foreffecting the close contact state becomes high, the apparatus must belarge, etc. due to the fact that

For example, in a case in which the pressure required to ensure closecontact between the master medium and the slave medium is 1-50 N/cm²(0.1-5.0 kg/cm²), and the slave medium is a 3.5 inch disk, in order toobtain the required pressure, an overall pressure of 70-3540N (7-354 kg)is required. The magnetic transfer apparatus must be designed so as tobe able to withstand this load, whereby the size of the apparatusbecomes larger. In a case, for example, in which a ring shapedelectromagnetic head is employed as a magnetic transfer apparatus forapplying the transfer magnetic field, the thickness of the conjoiningapparatus employed for bringing and maintaining the master and the slavemedium into the close contact state under pressure is increased, wherebyit becomes difficult to dispose the magnetic poles for applying themagnetic field adjacent to the respective contact surfaces of the mastermedium and the slave medium; the size of the magnetic field that isleaked becomes larger, and a magnetic field of a predetermined intensitydistribution cannot be applied, resulting in deficiencies in themagnetic transfer.

Further, even if the master medium is pressed against under uniformpressure by the entire surface of the slave medium, in actuality it isdifficult to achieve a uniform close contact state across the entiresurfaces thereof, due to various surface distortions and air remainingbetween the respective contact surfaces, whereby contact deficienciesare caused on portions of said contact surfaces, giving rise to transferdeficiencies. In particular, it has become clear that for cases in whichthe transfer pattern corresponding to the transfer data is not formeduniformly across the entire surface of the master medium, such as thatoccurring in the case of the servo pattern P shown in FIG. 7B describedbelow and which is formed in a radial pattern on portions of the surfaceof the master medium, that if good contact can be ensured for theportions on which this pattern occurs a favorable magnetic transfer canbe obtained.

In view of this problem, it is a further object of the present inventionto provide a magnetic transfer elastic pressing member for ensuring aclose contact pressure between the master and slave mediums, which isnot excessive when the magnetic transfer is to be performed, so as toimprove the contact therebetween and thus facilitate an improvement inthe quality of the transfer signal.

Further, another important issue regarding the performance of a magnetictransfer such as that described above relates to the necessity of highlyaccurate position matching of the respective contact surfaces of themaster and slave mediums. In particular, the center position of themagnetic pattern transferred and recorded on the slave medium must bematched with a high degree of accuracy to the rotational center of thedrive apparatus into which said slave medium is loaded after themagnetic transfer has been performed; for cases in which the transfersignal is a servo signal, there is a fear that an adequate trackingfunction will not be obtained if there is a large misalignment betweenthese positions.

As to the matching of the positions of the master and slave mediums, aconfiguration wherein the hole at the center position of the mastermedium and the hole at the center position of the slave medium areemplaced onto a center pin provided on a holder is structurallyfavorable.

For cases in which position matching is performed as described above, ifthe center positions of the master and slave mediums are misaligned, inaddition to the above-described problem, there is a fear that the mastermedium and/or the slave medium be damaged due to the center positionhole of the master slave medium being impacted against the side of thecenter pin of the holder when both the master and slave mediums areloaded thereon. Further, if the center positions of the master and slavemediums are misaligned, there is also a possibility that the contactpressure applied when the master medium and the slave medium areconjoined will not be uniform, whereby it becomes difficult to obtain auniform close contact state around the entire circumference. Stillfurther, there are also a problems related to the durability, and thelike, of the master and slave mediums due to the fact that a misalignededge portion that is brought into close contact with an end portion ofthe respective counterpart medium thereof can cause damage thereto.

The present invention has been developed in view of these types ofproblems, and it is a still further object of the present invention toprovide a magnetic transfer apparatus capable of conjoining a mastermedium and a slave medium so that a favorable magnetic transfer can beperformed therebetween.

Further, according to the positional adjustment of the master medium asdescribed above, because an operation is performed to match the centerpositions of the master and slave mediums by use of an image apparatuseach time the slave medium is exchanged and a magnetic transfer isperformed, a problem arises in that a loss of efficiency in the magnetictransfer is incurred due to the time consumed by this position matchingoperation.

Generally, a plurality of slave mediums are sequentially subjected to amagnetic transfer by a single master medium. In order to improve theefficiency of the magnetic transfer, it is preferable that: the mastermedium be set in the magnetic transfer apparatus in advance; the slavemedium be conveyed to the close contact position of the master medium;the master medium and the slave medium are conjoined to form a conjoinedbody; and then a transfer magnetic field is applied to the conjoinedbody. Here, for cases in which the slave medium is a hard disk or thelike, a central aperture is provided for the positioning thereof on therotational axis of the drive apparatus, and by matching the centerposition of the central aperture and that of the rotational center, thecentral aperture is supported by the slave medium support axis (thepositioning axis), whereby the accuracy of the position can be ensured.

The present invention has been developed in view of these types ofpoints, and it is a yet further object of the present invention toprovide a magnetic transfer method wherein the position matchingoccurring when a master medium and a slave medium are to be conjoined isimproved, and an increase in the productivity of the magnetic transferis gained thereby.

Further, as to the application of the transfer magnetic field, twomethods are considered: a first method, wherein the transfer magneticfield applying apparatus is fixed in place and the conjoined body formedby the master medium and the slave medium that have been brought intoand maintained in the close contact state is rotated; and a secondmethod, wherein the conjoined body formed by the master medium and theslave medium that have been brought into and maintained in the closecontact state is fixed in place and the transfer magnetic fieldapplication apparatus is rotated.

If the second method is utilized, for cases in which the transfermagnetic field application apparatus is an electromagnet apparatus orthe like, the apparatus includes a rotational driving mechanism inaddition to the magnetic field generating mechanism and becomes verylarge, and is therefore disadvantageous from the standpoints of thecumbersomeness thereof as equipment, the cost, and the like. Althoughthe first method does not have the problems described above which occursin the second method, when the mechanism in which it is possible toexchange the master medium and the slave medium is rotated as anintegral unit wherein the master medium and the slave medium aremaintained in the conjoined state, the rotational center of therotational axis thereof must be aligned with a high degree of accuracy.

For example, the pressing base plate on which the master medium issupported is moved into contact with the rotational base plate on whichthe slave medium is supported so as to conjoin the master medium and theslave medium and form a conjoined body thereby; if a misalignment occursbetween the rotational centers of the pressing base plate and therotational base plate when said pressing base plate and rotational plateare rotated as an integral unit, microscopic slippage occurs between themaster medium and the slave medium, and an accurate magnetic transfercannot be achieved. Further, for a case in which the contact between themaster medium and the slave medium is strong and no slippage occurstherebetween when the rotation operation is performed, although theaccuracy of the transfer can be maintained, with frequent use, problemsarise which impact the durability of the apparatus, such as increases indriving resistance, wear of components, and reduction in strength due tofatigue. This is because the misalignment of the rotational centers isabsorbed by repetitive deformation of the axis, bearings and the like ofthe apparatus.

Further, in performing a magnetic transfer, it is necessary that themaster and slave mediums be conjoined while in the state in which therotational center positions of both a single recording surface of theslave medium or both recording surfaces of the slave medium and thetransfer data bearing surface of the magnetic transfer master medium(s)are accurately matched; therefore, it is desirable that this operationis capable of being performed easily.

The present invention has been developed in view of the points describedabove, and it is a still yet further object of the present invention toprovide a magnetic transfer method wherein the operations of conjoiningand then rotating a master medium and a slave medium are performed sothat no slippage occurs between said master and slave mediums.

The magnetic transfer apparatus according to the present inventioncomprises: a master fixing base for positioning and supporting aposition of the master medium bearing a data signal; and a conjoiningapparatus for bringing a slave medium that is to receive the transfer ofthe data signal from the master medium into a state of close contact toform a conjoined body; wherein the master medium is exchanged as a wholewith each master fixing base.

The conjoining apparatus is provided with a pressing member for pressingthe slave member against the master medium, which is supported in thetransfer position by the master fixing base, so as to conjoin saidmaster and slave medium to form a conjoined body.

Further, it is desirable that a plurality of the master fixing bases,and a conveyor for sequentially conveying the master fixing bases to thetransfer position are further provided. In this configuration, a mastermedium is fixed into position in each master fixing base in advance, andeach master fixing base supporting a master medium is then set in theconveyor, and the master medium is exchanged along with each masterfixing base.

It is preferable that a master medium cleaning means is provided forcleaning dust and debris attached to the surface of the master mediumheld in the master fixing base. Here, the slave medium can also becleansed by use of a cleaning means, which can be the aforementionedmaster medium cleaning means or a separately provided cleaning means. Itis preferable that the cleaning means employ an ultrasound washing head;additionally, a gas bombarded with ultrasound vibrations, an ion airstream (de-electrified air), clean air, or the like may be blown ontothe surface of the slave medium to remove dust and debris therefrom. Themaster medium and the slave medium are cleaned directly before themagnetic transfer is to be performed, and the master medium is subjectedto further cleaning as required directly after contact.

A cleaning apparatus for cleaning the master fixing base removed fromthe conveyor together with the master medium can also be provided. As tothis cleaning apparatus, an apparatus employing: a liquid wash, whereinthe surface of the master and/or slave medium is washed with liquidbombarded with mega sonic vibrations by use of an ultrasound head; anultrasound vibration wash, wherein the surface of the master and/orslave medium is subjected to ultra sound vibrations, by use of anultrasound vibration head, within a liquid contained in a wash vat orwithin the air; blowing of an air stream that has been bombarded by useof ultrasound vibrations onto the surface of the master and/or slavemedium; a glide cleaning, performed by a glide head, after which anultrasound washing is performed thereon; an incineration wash, whereinthe surface of the master and/or slave medium is subjected to theemissions from an excimer laser; a plasma cleaning; or the like, can beemployed thereas.

Note that the slave medium can be positioned and supported in theholder, and the slave medium and the holder may be subjected to thecleaning process together, as the process preceding the magnetictransfer.

Further, the magnetic transfer apparatus according to the presentinvention comprises: a conjoining apparatus for hermetically sealing andconjoining a magnetic transfer master medium bearing a data signal and aslave medium having a magnetic recording portion for receiving themagnetic transfer from the master medium; a pressure applying means forapplying pressure that presses the slave medium against the mastermedium; a depressurizing means for reducing the pressure occurring inthe space between the master medium and the slave medium within theconjoining apparatus to obtain a degree of vacuum therebetween; and amagnetic field applying means for applying a transfer magnetic field;wherein, it is desirable that the conjoinment pressure applied by thepressure applying means when conjoining the master and the slave medium,and the degree of vacuum obtained by the depressurizing means are eachcontrolled independently.

Here, it is desirable that the pushing pressure be controlled in thestate in which the degree of vacuum has been controlled beforehand. Forexample, the degree of vacuum is controlled by the quantity of expelledair, and then the pushing pressure is controlled by the positions of theupper and lower chambers.

Note that when the master medium and the slave medium are beingconjoined, it is preferable that the degree of vacuum in their environsbe controlled to within the range of 50-100 kPa and that the conjoiningpressure be controlled to 0.01-49N/cm² (1-5000 gf/cm²).

Further, another magnetic transfer apparatus according to the presentinvention comprises: a conjoining apparatus for hermetically sealing andconjoining a magnetic transfer master medium bearing a data signal and aslave medium provided with a magnetic recording portion for receivingthe magnetic transfer from the master medium; a pressure applying meansfor applying pressure that presses the slave medium against the mastermedium; a depressurizing means for reducing the pressure occurring inthe space between the master medium and the slave medium within theconjoining apparatus to obtain a degree of vacuum therebetween; and amagnetic field applying means for applying a transfer magnetic field;wherein, it is desirable that the conjoining apparatus be provided witha lower chamber and an upper chamber, which is movable in the contactand separation directions relative to said lower chamber, and a sealelement for sealing the respective contact surfaces of both of saidchambers provided in a slidably contacting manner in a directionparallel to the contact and separation direction of said chambers so asto hermetically seal the interior space enclosed by said chambers in theconjoined state.

Further, it is desirable that the magnetic transfer elastic pressingmember according to the present invention is an elastic member forpressing against the back surface of a slave medium for receiving amagnetic transfer from a master medium to bring the data bearing surfaceof the master medium into close contact with a surface of the slavemedium, when a transfer magnetic field is to be applied to perform amagnetic transfer; wherein the pressing surface that contacts the backsurface of the slave medium is formed as an uneven pattern for pressingmainly against the portion thereof corresponding to the portion of therecording surface of slave medium conjoined with the transfer pattern ofthe master medium.

In this regard, it is advantageous that the elastic pressing membercomprises: an inner ring portion on the inner circumference thereof; anouter ring portion on the outer circumference thereof; and that aplurality of radial portions corresponding to the servo pattern of themaster medium concatenated with said inner ring portion and said outerring portion is formed as the protrusion pressure portions that connectwith the back surface of the slave medium.

Note that the magnetic transfer method consists of the steps of:pressing, by use of an elastic pressing member, the back surface of aslave medium having a magnetic recording portion for receiving thetransfer from a master medium having formed on a portion of thesubstrate thereof a transfer pattern corresponding to the data to betransferred, mainly against the portion corresponding to the transferportion to conjoin said master medium and said slave medium; andapplying a transfer magnetic field to said conjoined body to transferthe magnetic pattern, which corresponds to the transfer pattern, fromthe master medium to the slave medium.

When performing the magnetic transfer, it is advantageous that theinitial magnetization of the slave medium is performed in advance in theplanar track direction, in the case of planar recording, or an initialmagnetization current is applied in the perpendicular direction, in thecase of perpendicular recording; after which the initially magnetizedslave medium is conjoined with the master medium, and a transfermagnetic current is applied in the track direction in the directionopposite that in which the initial magnetization current has beenapplied, or in the perpendicular direction, to perform the magnetictransfer.

Further, the magnetic transfer apparatus of the present invention can bean apparatus for: conjoining both recording surfaces of a disk shapedslave medium that is to receive a magnetic transfer with the respectivedata bearing surface, on which a pattern corresponding to the data thatis to be transferred has been formed, of two disk shaped master mediums,each of which is disposed facing one recording surface of said slavemedium, and loading the conjoined body formed by said conjoined mediumsinto a holder and then applying the transfer magnetic field thereto toperform the magnetic transfer; wherein

the center positions of the master mediums and the slave medium arematched by use of a center pin provided on the holder, and it isdesirable that the amount of eccentricity of the center positions ofsaid master and slave medium is less than or equal to 100 um.

At this point, it is more desirable that the eccentricity of the centerpositions of said master and slave medium is less than or equal to 50um.

Further, according to the magnetic transfer method of the presentinvention, wherein the data bearing surface of a disk shaped mastermedium on which a pattern corresponding to the data to be transferred isbrought into close contact with a recording surface of a slave mediumformed of a disk shaped magnetic recording medium for receiving thetransfer from said master medium to form a conjoined body, and atransfer magnetic field is applied to said conjoined body to perform amagnetic transfer; it is desirable that the master medium be adjustablypositioned on the outer circumference of the slave medium support axisfor determining and supporting the position of the central aperturewhich has been opened on the slave medium, and that after the centerposition of the pattern formed on said master medium has been matched tothe position of the center position of the slave support axis and fixedin the matched position, the slave medium is supplied to the slavesupport axis and the position matching between the master and slavemedium is performed.

At this point, it is desirable that the position of the pattern of themaster medium is visually measured by use of a measuring microscope, andthat the center position of the pattern of the master medium is thenmatched with the center position of the slave support axis. Further, aposition matching mark can be provided along with the transfer patternformed on the master medium; said mark can then be visually measured byuse of a measuring microscope, and the center position of the pattern ofthe master medium matched with the center position of the slave supportaxis.

Further, the magnetic transfer apparatus implementing the magnetictransfer method according to the present invention is an apparatus forbringing into close contact the data bearing surface of a disk shapedmaster medium on which a pattern corresponding to the data to betransferred has been formed, with a recording surface of a slave mediumformed of a disk shaped magnetic recording medium for receiving thetransfer from said master medium to form a conjoined body, and applyinga transfer magnetic field to said conjoined body to perform a magnetictransfer; further comprising a first base plate on the master mediumside, a second base plate on the slave medium side, a slave support axisfor determining and supporting the position of the slave centralaperture provided at the center position of the slave medium of thefirst base plate, and a master support member capable of adjusting thefirst base plate in the x, y directions provided on the outercircumference of the slave support axis, wherein it is desirable thatthe master support member be a member that is fixed in place after thecenter position of the pattern formed on the master medium supportedtherein has been matched with the center position of the slave supportaxis, and are in a state in which the positions are matched.

It is advantageous that the first base plate be removably provided, andthat the first base plate be removed from the transfer position when theposition of the master medium is to be matched. At this time, thepattern or the mark of the master medium is visually measured by use ofa measuring microscope, and the center position of said pattern ismatched to the center position of the slave support axis.

As to the measuring microscope, a microscope provided with a stage thatis movable in the x, y directions; wherein, if a plurality of points areplotted while the surface of the subject master medium is observed, anearly circular area is described and the center position thereof can beobtained, can be used therefor. After the first base plate is placed onthe stage and a master medium is loaded and supported in the mastersupport member thereof, the center position of the slave support memberis obtained and the center position of the pattern formed on the mastermedium is obtained from the pattern or from the mark in the same manner,and the position of the master medium is adjusted in the x, y axes ofthe slave support medium so as to match both of said center positions.

Further, the magnetic transfer apparatus according to the presentinvention comprises a pressure applying means for pressing a mastermedium and a slave medium, of which the positions thereof have beenmatched, together so as to conjoin said master and slave medium to forma conjoined body, and a magnetic field applying means for applying atransfer magnetic field to the conjoined body formed of theposition-matched master medium and the slave medium, etc. It isadvantageous that the fixing of the position of the master mediumsupported in the master support member be performed by a suctionfixation process or the like.

An electromagnet apparatus or a permanent magnet apparatus can be usedas the magnetic field applying means: the magnetic field applying meansapplies a transfer magnetic field to one or both sides of the contactportion of the master medium and the slave medium; the conjoined bodyformed by the master and the slave medium or the transfer magnetic fieldis rotated relative to each other and the magnetic transfer performed.

Further, the magnetic transfer method according to the present inventionis a method comprising the steps of: bringing a master medium bearing adata signal and a slave medium formed of a magnetic recording medium forreceiving the transfer into close contact to form a conjoined body; andapplying a transfer magnetic field thereto, while said conjoined body isbeing rotated, to perform a magnetic transfer; wherein, it is desirablethat the master medium and the slave medium are conjoined by pressurefrom a pressure applying means, and that said pressure applying meansexerts no constraint on the force component in the rotational directionwhen the conjoined body formed thereby is rotated as an integral unit bythe rotational drive of a rotational driving means.

Here, the pressure applying means is a means for moving the slave mediumor the master medium in the contact and separation directions to conjointhe master and slave medium, and it is preferable that the each of theslave medium and the master medium are supported on a pressure bearingsubstrate. Further, the rotation driving means is a means for rotatingthe conjoined body formed by the conjoined master medium and slavemedium as an integral unit, and it is preferable that the rotationalforce be transferred by the conjoining force of both the master mediumand the slave medium, or by a motive force transferring mechanism.

Further, the magnetic transfer apparatus implementing the magnetictransfer method according to the present invention is an apparatus forbringing into close contact the data bearing surface of a disk shapedmaster medium on which a pattern corresponding to the data to betransferred has been formed with the a recording surface of a slavemedium formed of a disk shaped magnetic recording medium for receivingthe transfer from said master medium to form a conjoined body, andapplying a transfer magnetic field to said conjoined body to perform amagnetic transfer; wherein it is preferable that said apparatus furthercomprises a rotational base plate for supporting and rotating the mastermedium or the slave medium, a pressing base plate for pressing againstthe master medium or the slave medium, a pressure applying base forsupporting the pressing base plate and which is capable of moving thepressing base plate in a conjoining-separating direction in relation tothe rotational base plate, and a pressure transferring mechanism thatdoes not constrain the force component occurring in the rotationaldirection between the pressing base plate and the pressure applyingbase.

It is advantageous that the pushing pressure transferring mechanism isconfigured of a thrust bearing construction that has been presscontacted via a ball bearing or the like, or of an air gap that expelspressurized air. Accordingly, it is preferable that the pressing baseplate is rotated with the rotational base plate by the conjoining forceor the rotational force transfer mechanism, and that the pressureapplying base is fixed in the rotational direction. A mechanism forrotationally driving the rotational axis of the rotational base plate isprovided, and the pressing base plate is rotated via the rotational baseplate.

At this time, the slave medium or the master medium is positioned in therotational base plate and supported therein, and the master medium orthe slave medium is positioned in the pressing base plate and supportedtherein; wherein, it is preferable that a positioning means be providedbetween both the rotational base plate and the pressing base plate, andthat the positioning of the master medium and the slave medium beperformed thereby.

Further, according to the magnetic transfer apparatus of the presentinvention, it is preferable that a positioning mechanism, which isprovided with a positioning pin or a positioning hole is provided on therotational base plate or the pressing base plate on which the slavemedium is positioned and supported, and provided with a positioning holeor a positioning pin on the rotational base plate or the pressing baseplate on which the master medium is positioned and supported, isprovided.

Here, the master medium can be provided at a size larger than the slavemedium, and a positioning mechanism for matching the position of therotational base plate or the pressing base plate supporting the slavemedium and the position of the master medium can be provided on theportion of the master medium that is not to be brought into contact withthe slave medium. Further, a positioning mechanism can be provided formatching the position of the rotational base plate or the pressing baseplate supporting the slave medium at the center portion thereof and theposition of the master medium. The positioning mechanism comprises apositioning pin on one side and a positioning hole on the other side,wherein it is preferable that the distal end of the positioning pin istapered. It is preferable that the positioning pin be provided as aplurality of pins along the outer circumference, or as a single pinlocated at the center position.

As to the magnetic field applying apparatus, although an electromagnetapparatus or a permanent magnet apparatus can be employed therefor, fromthe standpoint of setting and adjusting the intensity of the magneticfield and other conditions, it is preferable that an electromagnetapparatus be employed. The magnetic field applying apparatus is a meansthat generates a magnetic field in the direction parallel to the trackdirection within the range extending in the radial direction of theslave medium, and the magnetic transfer is performed on the entiresurface of the slave medium by rotating the conjoined body formed by themaster medium and the slave medium brought into and maintained in closecontact.

As to the performance of the magnetic transfer, there are cases in whichthe slave medium is conjoined with the master medium and the transfer isperformed successively on one surface of the slave medium at a time, andcases in which a master medium is conjoined to each of both sides of theslave medium and the transfer is performed concurrently on both sides ofthe slave medium. In the case of the single surface successive transfer,the slave medium (or the master medium) is supported in the rotationalbase plate, and the master medium (or the slave medium) is supported inthe pressing base plate. In the case of the double-sided transfer, afirst master medium is supported in the rotational base plate and asecond master medium is supported in the pressing base plate, and theslave medium is sandwiched therebetween. In this manner, one side orboth sides of the slave medium is brought into close contact with amaster medium, and a magnetic field applying apparatus is disposed onone or both sides of the slave medium and the transfer magnetic field isapplied.

Note that according to the magnetic transfer method, it is preferablethat the slave medium is first subjected to an initial magnetization inthe track direction thereof by use of a direct current magnetizationprocess, wherein the slave medium is brought into close contact with themagnetic layer that has been formed over the uneven pattern, whichcorresponds to the transfer data, of the master medium, and a transfermagnetic field is applied in the direction substantially opposite thatin which the initial magnetizing current has been applied to the surfaceof the slave medium, to perform the magnetic transfer. It isadvantageous that the data signal be servo data.

According to the present invention as described above, a master fixingbase for fixing the position of the master medium and supporting themaster medium in said fixed position, and a conjoining apparatus forbringing the slave medium into close contact with the master medium toform a conjoined body are provided; wherein, by making the master mediumexchangeable along with each master medium position fixing base, itbecomes unnecessary to position the conjoining apparatus when only themaster medium is to be exchanged, whereby the operational efficiency inperforming the transfer is improved because the time required toexchange the master medium can be shortened, and the productivity ofpreformatted slave mediums can thereby be improved.

Further, for cases in which a plurality of master medium position fixingbases are provided, and a conveyor for sequentially moving the mastermedium position fixing bases to the transfer position is furtherprovided, the time efficiency in transferring the master mediums can beimproved a level, and the magnetic transfer operating efficiency can beimproved.

Still further, if a cleaning means for removing foreign matter thatbecomes attached to the surface of the master medium supported in themaster medium position fixing base is further provided, cleaning of themaster medium is performed directly before the magnetic transfer isperformed, the removal of foreign matter that has become attached to thesurface of the master medium during the exchange of the master fixingbase or the conveyance thereof becomes possible, so that the foreignmatter attached to the surface of the master medium when the transfer isto be performed is minimized, whereby transfer deficiencies can beprevented, magnetic transfers exhibiting stable quality characteristicscan be performed, and reliability can be improved.

On the other hand, if a cleaning apparatus for washing the master mediumtogether with the master fixing base, in which said master medium issupported, upon the removal of said master fixing base from theconveyor, together with the above-described prevention of transferdeficiencies by the removal of foreign matter form the surface of themaster medium, the operational efficiency is further improved becausethe operation of removing the master medium is not performed when theexchange or cleaning thereof is performed.

Further, according to the present invention: the master medium and theslave medium are brought into close contact and conjoined by theconjoining apparatus; a pressing means applies pressure against theslave medium to press the slave medium against the master medium and adepressurizing means depressurizes the sealed space formed therebetweento obtain a vacuum; wherein, for cases in which the conjoinment pressureof the master medium and the slave medium due to the pushing pressure ofthe pressing means, and the degree of vacuum due to a depressurizingmeans are each controlled independently optimal conjoinment conditionscan be obtained, complete contact of the master medium and the slavemedium can be ensured across the entirety of the respective contactsurfaces thereof, the generation of signal omissions caused by contactdeficiencies between the master medium and the slave medium can beprevented and favorable transfers free of blemishes and the like can beperformed, and even if the degree of vacuum increases, there is noexcessive increase in the pushing pressure, whereby a deterioration ofthe durability of the master medium can be prevented, and the degree ofvacuum can be increased so as to prevent air from remaining between thecontact surfaces.

In particular, in the state in which air has been expelled from theconjoinment space and the degree of vacuum controlled beforehand, if themaster medium and the slave medium are conjoined and the conjoinmentpressure controlled, no air remains on either of both of the respectivecontact surfaces, whereby the contact therebetween can be furtherimproved, leading to an improvement in transfer quality.

Further, if the conjoining apparatus is provided in a configurationcomprising a seal element in sliding contact with the surfaces parallelto the contact and separation directions of a lower chamber and an upperchamber that are movable relatively in the conjoining direction thereof,so as to hermetically seal the interior space enclosed by said chambersin the conjoined state, the configuration favorably facilitates the easyindependent control of each of the conjoinment pressure and the degreeof vacuum.

Still further, even for cases in which the thickness of the elasticmember for pressing the slave medium against the master medium, which isprovided as required, changes, the form of the upper chamber and thelower chamber of the conjoining apparatus, and the like, does notchange, and it is possible to independently control each of theconjoinment pressure and the degree of vacuum occurring when themagnetic transfer is to be performed.

In addition, according to the present invention, for cases in which thepressing surface of the elastic pressing member for pressing against theback surface of the slave medium so as to conjoin said slave medium withthe master medium is formed in an uneven form for pressing mainly thecontact portion corresponding to the pattern of the master medium, thepressure required for the contact portion can be ensured while reducingthe overall pressing force, and a further improvement in contact can beobtained because the pressure on the portion corresponding to thedepression portions of the elastic pressing member is low and can serveas a channel through which air can escape; whereby the generation ofsignal omissions caused by contact deficiencies between the mastermedium and the slave medium can be prevented, and the quality of thetransfer signal as well as the reliability can be improved.

That is to say, for cases in which the transfer data is a servo signal,for example, and the percentage of the entire surface area of the mastermedium occupied by the surface area of the transfer pattern formedthereon is 10% or less and the pressing surface area of the uneven formon the elastic pressing member, which corresponds to the transferpattern, is formed on 10% or less of the entire surface the slavemedium, the entire pushing force required to achieve a contact forcebetween the master medium and the slave medium of 50 N/cm² (5.0 kg/cm²)can be reduced to {fraction (1/10)} of the 354 N (35.4 kg) required ifthe entire surface is to be pressed for cases in which the slave mediumis a 3.5 inch disk; the thickness, etc., of each load bearing componentbecomes smaller, and the apparatus can be made more compact. Further,the magnetic poles occurring in the magnetic field applying apparatuscan be provided adjacent to the contact surface of the master medium andthe slave medium, whereby the intensity of the leakage magnetic fieldbecomes smaller, and a magnetic field having a predetermined magneticfield distribution can be applied to perform a favorable magnetictransfer.

Further, according to the present invention, when the disk shaped slavemedium and two disk shaped master medium are brought into close contactso that the slave medium is sandwiched by the master mediums to performa magnetic transfer, the center positions of both of said two mediumsare aligned by the center pin provided on the holder, and for cases inwhich the eccentricity between the center positions of the master andslave mediums is less than or equal to 100 um, uniform contact can beobtained across the entirety of the respective contact surfaces thereof,damage due to contact on only one side can be prevented, and damage tothe edge portions can be prevented, whereby the durability of the mediumcan be improved.

More particularly, if the eccentricity between the center position ofthe master medium and the center position of the slave medium is lessthan or equal to 50 um, a highly accurate transfer can be ensured.

Further, according to the present invention, if the master medium isadjustably disposed on the outer circumference of the slave support axisthat determines and secures the position of a central aperture of theslave medium, for cases in which the slave medium is supplied to theslave support axis after the center position of the pattern formed onsaid master medium has been aligned with the center position of saidslave support axis and fixed in said aligned position, and then thepositioning of the master medium and the slave medium is performed, thecenter position of the slave support axis, which serves as therotational center of the slave medium when the slave medium is loadedinto a drive apparatus, can be matched with a high degree of accuracy tothe center position of the pattern formed on the master medium, wherebytogether with an increase in reliability, an improvement in magnetictransfer efficiency is gained as the need to align the position of theslave medium each time that a slave medium is supplied is eliminated.

Further, if pattern formed on the master medium is visually measured byuse of a measuring microscope, the center position of said patternformed on the master medium is matched to the center position of theslave support axis, the position matching can be performed easily andwith a high degree of accuracy.

If a positioning mark is provided along with the formation of thetransfer pattern on the master medium, the base setting occurring in theposition matching of the master medium becomes simple and the operationof adjusting the position by use of the measuring microscope becomeseasier.

Further, by providing the magnetic transfer apparatus with a first baseplate on the master medium side, a second base plate on the slave mediumside, a slave support axis for determining and maintaining the positionof the central aperture of the slave medium, and a master supportmember, which is positionally adjustable in the x, y directions,disposed on the outer circumference of the slave support axis, theabove-described operation for accurately matching the respective centerpositions of the master medium and the slave medium becomes easy, and ahighly efficient magnetic transfer can be realized.

If the first base plate is provided so as to be attachable andremovable, and is removed from the transfer position when matching theposition of the master medium, the position matching operation can beeasily performed by use of a measuring microscope or the like.

Further, according to the present invention, when the master medium andthe slave medium have been conjoined and the conjoined body formedthereby is rotated and the transfer magnetic field is applied thereto toperform magnetic transfer, for cases in which a configuration has beenprovided so that the force component, of the pressure between the mastermedium and the slave medium, occurring in the rotational direction ofthe conjoined body is not constrained, no misalignment occurs betweenthe rotating side and the pressurized side, and the master medium andthe slave medium forming the conjoined body can be rotated as anintegral unit, whereby an accurate magnetic transfer can be performed,and as there is no deformation of the apparatus due to repetitiveoperation, the durability thereof is improved.

Still further, if the substrate that supports the slave medium anddetermined the position thereof is matched to the master medium by useof a positioning mechanism, the operation for matching the respectivecenter positions of both the master medium and the slave medium can besimplified, and an accurate magnetic transfer can be efficientlyperformed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic drawing of a magnetic transfer apparatus accordingto an embodiment of the present invention,

FIG. 2 is a schematic drawing of the conjoining apparatus portionoccurring in another embodiment of the present invention,

FIG. 3 is a perspective view of the main portion of the transfer stateof a magnetic transfer apparatus according to another embodiment of thepresent invention,

FIG. 4 is a cross-sectional view of a conjoining apparatus,

FIG. 5 is a perspective view of the main portion of the transfer stateof a magnetic transfer apparatus according to yet another embodiment ofthe present invention,

FIG. 6 is an exploded view of a conjoining apparatus,

FIGS. 7A and 7B are plan views of an elastic pressing member and amaster medium, respectively, according to still yet another embodimentaccording to the present invention,

FIG. 8 is a perspective view of the main portion of the transfer stateof a magnetic transfer apparatus according to yet another embodiment ofthe present invention,

FIG. 9 is an exploded view of the holder shown in FIG. 8,

FIG. 10 is a drawing illustrating eccentricity between the centerpositions,

FIG. 11 is a perspective view of the main portion of the transfer stateof a magnetic transfer apparatus according to still yet anotherembodiment of the present invention,

FIG. 12 is a cross-sectional view of a magnetic transfer apparatus inthe conjoined state,

FIG. 13 is a schematic drawing of a measuring microscope for use inadjusting the position of the master medium,

FIG. 14 is a schematic plan view of a master medium in the state priorto the adjustment of the position thereof,

FIG. 15 is a schematic plan view of a master medium in the statesubsequent to the adjustment of the position thereof,

FIG. 16 is a cross-sectional view of the main part of an embodiment of amagnetic transfer apparatus prior to the conjoined state,

FIG. 17 is a plan view of a master medium according to anotherembodiment of the present invention,

FIG. 18 is a cross-sectional drawing of the main part of anotherembodiment of a magnetic transfer apparatus prior to the conjoinedstate,

FIG. 19 is a schematic cross-sectional view of a magnetic transferapparatus implementing yet another magnetic transfer method according tothe present invention,

FIG. 20 is a plan view of the pressure base shown in FIG. 19,

FIG. 21 is a cross-sectional view of the main part of a magnetictransfer apparatus having another embodiment of a pressing forcetransfer mechanism according to the present invention,

FIG. 22 is a schematic drawing of the rotational base plate and thepressing substrate, which are provided with a positioning mechanism,according to another embodiment t of the present invention,

FIG. 23 is a plan view of the master medium of FIG. 22, and

FIG. 24 is a schematic drawing of the rotational base plate and thepressing substrate, which are provided with a positioning mechanism,according to yet another embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, the preferred embodiments of the present invention will beexplained with reference to the attached drawings. FIG. 1 is a schematicdrawing of the magnetic transfer apparatus according to an embodiment ofthe present invention.

The magnetic transfer apparatus 1 shown in FIG. 1 comprises: a lowermaster fixing base 11 for supporting a master medium 3, which bears adata signal; a conjoining apparatus 5 that is provided with an upperpressing member 12 for pressing the slave medium 2, of which the centerposition thereof is in the position matched state, having a magneticrecording portion for receiving the transfer from the master medium 3,against said master medium 3 to form a conjoined body; a conveyor 6,which is provided with a plurality of master fixing bases 11, forsequentially moving the plurality of master fixing bases to the transferposition; and a cleaning means 7 for removing foreign matter thatbecomes adhered to the master medium 3 supported in a master fixing base11. Further, the magnetic transfer apparatus 1 further comprises apressing means (not shown) for applying pressure to the conjoiningapparatus 5, and a magnetic field applying apparatus (not shown) forapplying a magnetic field to the conjoined body while rotating theconjoining apparatus 5.

Each master medium 3 is positioned and maintained in said positionwithin each master fixing base 11, and these master fixing bases 11 arethen set in the conveyor 6; when the master medium 3 is to be exchanged,the master fixing base 11 as a whole is exchanged from the conveyor 6.

The conveyor 6 (an index table) is supported on a rotational axis 14located at the center position of a disk shaped table 13. The table 13comprises three master fixing base 11 support portions 15, and is movedbetween a transfer position, an exchange position, and a cleaningposition by a rotational drive means (not shown). Note that the numberof support portions 15 provided on the conveyor 6 is not limited tobeing of three locations.

The cleaning means 7 provided at the aforementioned cleaning positioncomprises an ultrasound washing head 16 for blowing a liquid or a gas,which has been agitated by ultrasonic vibrations, onto the surface of amaster medium 3; the cleaning means 7 performs the cleaning operation onthe master medium 3 supported in the master fixing base 11 that has beenmoved to the cleaning position, which directly precedes the transferposition, by the rotation of the conveyor 6, and thereby removes theforeign matter adhering to the surface of said master medium 3. Notethat the cleaning means can be a means that blows an ion wind(de-electrified air) or a clean air burst onto the surface of the mastermedium 3. For cases in which the cleaning is performed as a wet process,an IPA liquid, an IPA steam, or dry air blown onto the surface, etc.,can be used to dry said surface of the master medium 3.

The master fixing base 11 is disk shaped, and is provided with an uppersurface 11 a, which has an outside diameter larger than that of themaster medium 3; the lower surface of the master medium 3 is supportedby suction or the like on the center portion of this upper surface 11 a.In the same manner, the upper pressing member 12 is also disk shaped,and is provided with a lower surface 12 a, which is larger than theoutside diameter of the slave medium 2; this upper pressing member 12 ismovable in the upper and lower directions, i.e., the contact andseparation directions with respect to the master fixing base 11, and isprovided so as to press the slave medium 2 onto the master medium 3 toform a conjoined body therewith. Note that a sheet-form elastic elementcan be attached to the lower surface 12 a of the upper pressing member12, and the slave medium 2 can be pressed via this elastic element.

Further, a rotational axis portion 11 b and a rotational axis portion 12b are provided protruding from the bottom surface of the master fixingbase 11 and the upper surface of the upper pressing member 12,respectively. This master fixing base 11 and upper pressing member 12are rotated integrally by a rotation mechanism (not shown) duringmagnetic transfer.

The pressing means (not shown) is provided with a pressure cylinder, andthe distal end of the pressure rod thereof applies a predeterminedpressure load to the pressing member 12 of the conjoining apparatus 5.Note that because the conjoining apparatus 5 is rotated while in theconjoined state, the pressure is made to act on the rotational axisportion 12 b of the pressing member 12.

When the magnetic transfer operation is to be performed, initial directcurrent magnetization of the slave medium is performed in advance in theplanar track direction, in the case of planar recording, or in theperpendicular direction, in the case of perpendicular recording. Thisslave medium 2, which has been subjected to the initial magnetization,is brought into close contact with the master medium 3 to form aconjoined body, and a transfer magnetic field is applied thereto in thedirection opposite that in which the initial direct currentmagnetization has been applied, or in the perpendicular direction, toperform the magnetic transfer.

A disk shaped magnetic recording medium such as a hard disk, a highdensity flexible disk, or the like, provided with a magnetic recordingportion (a magnetic layer) on one or both faces thereof, is employed asthe slave medium 2. The magnetic recording portion thereof is either amagnetic recording layer that has been coated onto the surface thereof,or a magnetic recording layer of thin metallic film formed on thesurface thereof.

The master medium 3 is formed as a discoid shape from a hard material.This master medium 3 comprises a pliable magnetic layer that has beenformed over a micro uneven pattern formed on the surface of a substrate;this surface becomes the transfer data bearing surface on which thetransfer pattern that is to be brought into close contact with therecording surface of the slave medium 2 has been formed. The face of themaster medium 3 opposite this transfer data bearing face is supported onthe master fixing base 11.

A synthetic resin, a ceramic material, an alloy, aluminum, glass,quartz, silicon, nickel, or the like is used to form the substrate ofthe master medium. The uneven pattern can be formed by use of a stampingmethod or the like. The pliable magnetic layer is formed of a magneticmaterial by use of a vacuum film forming means such as a vacuumdeposition method, a sputtering method, an ion platting method, or by ametal plating method, etc. A substantially identical type of mastermedium is used in both planar recording and perpendicular recording.

In a case, for example, in which planar recording is to be performed,the magnetic field applying apparatus (not shown) for applying atransfer magnetic field or an initial magnetic field comprises a ringshaped electromagnetic head disposed on both the upper and lower sidesof the conjoined body, that applies a transfer magnetic field generatedparallel to the track direction in the same direction from both theupper and lower sides. The magnetic field applying apparatus can also beprovided so as to be rotatable. The magnetic field applying apparatuscan be provided on only one side of the conjoined body, or can be apermanent magnet apparatus provided on both sides of the conjoined body.Further, the magnetic field applying apparatus used for cases in whichperpendicular recording is to be performed can comprise electromagnetsor permanent magnets of different polarities disposed in the upper andlower sides of the conjoining apparatus 5, respectively, wherein thetransfer magnetic field is generated in the perpendicular direction andapplied. If the magnetic field is applied partially to only a portion ofthe surface, either the conjoining apparatus 5 or the magnetic field isrotated to perform the magnetic transfer across the entirety of thesurface.

As shown in FIG. 2, the magnetic transfer apparatus 1 can be providedwith a cleaning means 8 at the transfer position thereof, that is, as aportion of the conjoining apparatus 5, for subjecting the master medium3 to a cleaning process directly preceding the performance of themagnetic transfer. Further, the master medium 3 can be cleaned directlyafter loading thereof at the transfer position.

The cleaning means 8 shown in FIG. 2 comprises an ultrasound washinghead 17 disposed in the vicinity of the transfer position and so as tobe movable toward and away from the conjoining apparatus 5. Theultrasound washing head 17, in the same manner as described above, is awashing head that blows a liquid or a gas that has been agitated byultrasonic vibrations, or a washing head that blows an ion wind(de-electrified air) or clean air onto the surface that is to becleaned. Then, the ultrasound washing head 17 is moved over the mastermedium 3 which is supported in the master fixing base 11 and performsthe cleaning operation thereon, while the upper pressing member 12 is inthe open state, after which it is withdrawn to the standby position.

Further, the slave medium 2 can be cleaned directly preceding theconjoinment thereof with the master medium 3. The cleaning of the slavemedium 2 can be performed by the same cleaning means 8 used for cleaningthe master medium 3, or by a different cleaning means.

The magnetic transfer apparatus 1 is an apparatus for performing amagnetic transfer from the same master medium 3 to a plurality of slavemediums 2; wherein first, a master medium 3 is positioned and supportedin each of a plurality of master fixing bases 11, and this plurality ofmaster fixing bases 11 is set into a conveyor 6. Then, before beingmoved to the transfer position, the master medium 3 supported in themaster fixing base 11 is cleaned by the cleaning means 7. After saidmaster medium 3 has been cleaned by the cleaning means 8, the masterfixing base 11 in which said master medium 3 is supported is moved tothe transfer position by the rotation of the conveyor 6, and after thecenter position of a slave medium 2, which has been initially magnetizedin the planar direction or in the perpendicular direction, is alignedwhile the pressing member 12 is in the open state wherein there is a gapseparating said pressing member 12 and the master fixing base 11, thepressing member 12 of the conjoining means 5 is moved toward the masterfixing base 11 and the master medium 3 and the slave medium 2 areconjoined under a predetermined pressure by the pressure applying means.The cleaning means 8 shown in FIG. 2, if provided, cleans the mastermedium 3 (and the slave medium 2) immediately preceding said conjoinmentof said master medium 3 and slave medium 2.

Then, the magnetic field applying means is made to approach the upperand lower sides of the conjoining means 5, and a transfer magnetic fieldis applied, while the conjoined body is rotated, in the directionsubstantially opposite that in which the initial magnetic field wasapplied, to transfer and record the magnetic pattern corresponding tothe transfer pattern formed on the master medium 3 to the magneticrecording portion of the slave medium 2.

The transfer magnetic field applied when the magnetic transfer isperformed is absorbed by the pattern of the protrusion portions formedby the pliable magnetic body of the transfer pattern on the mastermedium 3 conjoined with slave medium 2, and as a result: in the case ofplanar recording, the initial magnetization of this portion is notinverted, whereas the initial magnetization of the other portions isinverted; in the case of perpendicular recording, the initialmagnetization of this portion is inverted, whereas the initialmagnetization of the other portions is not inverted, and the magneticdata corresponding to the transfer pattern formed on the master medium 3is transferred and recorded on the slave medium 2.

Then, when magnetic transfer has been performed a predetermined numberof times, and an irregularity such as foreign matter becoming adhered tothe surface of the master medium 3 or slave medium 2, or transferdeficiencies or the like occurs, the conveyor is rotated and a newmaster fixing base 11, having just been cleaned, is moved to thetransfer position, and then the next magnetic transfer is performed incontinuation in the same manner as described above.

The master fixing base 11 that has been moved from the transfer positionto the standby position is removed according to its state from theconveyor 6 and exchanged. When the exchange is performed, the masterfixing base 11 as a whole is removed from the conveyor 6, and a masterfixing base 11 supporting a new master medium 3 is set therein. Further,for cases in which a master medium 3 can be reused after being cleanedby the cleaning means 7, the exchange is not performed.

Further, as to master fixing bases 11 that have been removed from theconveyor 6, the master mediums 3 supported in each of said removedmaster fixing bases 11 can be cleaned by use of a separately providedcleaning apparatus. This cleaning apparatus may be provided instead ofthe cleaning means 7, or they can be provided so that both performcleaning.

The master mediums 3 can be cleaned by this cleaning means by, forexample, being submersed into the wash liquid contained within a washtub while still being supported in their respective master fixing bases11, and agitating said wash liquid with ultrasound vibrations from anultrasound head, whereby the foreign matter adhered to the surface ofthe master medium 3 removed. Alternatively, a liquid washing by a liquidthat has been bombarded by megasonic vibrations from an ultrasoundwashing head, an atmospheric washing by ultrasound vibrations from anultrasound head, a glide cleaning employing a glide head, an ultrasoundwash performed after a glide cleaning is carried out, an incineratingwash by the light emitted from an excimer laser, a plasma cleaning, orthe like can be employed.

Note that the slave medium 2 can be supported in a holder (not shown)and the slave medium 2 can be cleaned together with said holder in theprocess preceding the magnetic transfer.

According to the current embodiment: the conveyor 6 is provided with aplurality of master fixing bases 11, each of which determines andmaintains the position of a master medium 3 supported therein; themaster medium is sequentially cleaned by a cleaning means 7 and acleaning means 8, and moved to the transfer position, in which themagnetic transfer is then performed; wherein, because the master medium3 is exchanged along with the magnetic transfer master fixing base 11,exchanging the master mediums 3 is easy, and the operational efficiencythereof is high, whereby an improvement in production efficiency isobtained, and the occurrence of transfer deficiencies can be preventedby the cleaning of the master medium immediately prior to theperformance of the magnetic transfer, enabling the performance of a highquality magnetic transfer. Further, even for cases in which the mastermedium 3 is washed together with the master fixing medium removed fromthe conveyor 6, the operational efficiency can be improved because themaster medium is not removed from the master fixing base 11 when theexchange and cleaning thereof is performed.

Next, another embodiment according to the present invention will beexplained. FIG. 3 is a perspective view of the main part of a magnetictransfer apparatus in the transfer state according to the currentembodiment. FIG. 4 is cross-sectional view of the conjoining apparatusaccording to the current embodiment. Note that each drawing is a modeldrawing, and the actual dimensions of each of the portions shown thereinare of a different ratio.

The magnetic transfer apparatus 20 shown in FIG. 3 comprises: alower-side chamber 31 and an upper-side chamber 32; a conjoiningapparatus 25 provided with an elastic element 24 disposed on the innerportion thereof, as shown in FIG. 4, for conjoining a slave medium 23and a master medium 23 of which the center positions thereof are in theposition matched state; a pressing means 26 for applying pressure to theconjoining means 25; a decompressing means 27 (refer to FIG. 4) forremoving air from the interior of the conjoining means 25 anddecompressing the inner portion thereof; and a magnetic field applyingapparatus 28 for applying a magnetic field while rotating the conjoiningapparatus 25. The degree of vacuum, which is provided by thedecompressing means 26, within the conjoining apparatus 25, and thepressure on the slave medium 22 and the master medium 23, which isprovided by the pressing means 26, are each controlled independently.

The lower chamber 31 of the conjoining means 25 is disk shaped, and hasa disk shaped upper surface 31 a that is larger than the outer diameterof the master medium 23; the lower surface of the master medium 23 issupported on the center portion of this upper surface 31 a by suction orthe like. The upper chamber 32 is disk shaped, and has a disk shapedlower surface 32 a that is larger than the outer diameter of the slavemedium 22; a sheet shaped elastic element 24 is attached to this lowersurface 32 a, and the slave medium 22 is supported on the lower surfaceof this sheet shaped elastic element 24. The upper chamber 32 is movablein the vertical direction so as to be separated and brought into contactwith the lower chamber 31, and is provided so as to press the slavemedium 22 onto the master medium 23 to form a conjoined body. Note thatthe slave medium 22 can also be set above the master medium 23.

An upwardly protruding flange portion 31 b is provided on the outercircumference of the lower chamber 31, and a downwardly protrudingflange portion 32 b is provided on the outer circumference of the upperchamber 32. The diameter of the outer circumferential surface of theflange portion 32 b of the upper chamber 32 is smaller than the diameterof the inner circumferential surface of the flange portion 31 b of thelower chamber 31, and the flange portion 32 b of the upper chamber 32 isprovided so as to be insertable into the inner circumference side of theflange portion 31 b of the lower chamber 31 (the size relation betweenthe respective flange portions can be reversed) Further, a seal element33, which is an O-ring, is installed around the outer circumference ofthe flange portion 32 b of the upper chamber 32, and when the upperchamber 32 is moved toward the lower chamber 31, this seal element 33slidably contacts the inner circumference surface of the flange portion31 b of the lower chamber 31, serving to seal off the surfaces in thedirection substantially parallel to that of the contact and separationdirections (the axial direction), thereby hermetically sealing the spacewithin the interior of both the lower chamber 31 an the upper chamber32. The seal element 33 can also be installed o the lower chamber 31.

The upper chamber 32 and the lower chamber 31 are provided so as to bemovable in the aforementioned axial direction when in the state whereinthe interior portion of said upper chamber 32 and lower portion 31 ishermetically sealed by the seal element 33. Further, the hermeticallysealed state is ensured even if the height of the conjoined body formedby the master medium 23 and the slave medium 22 changes due to a changein the thickness of the elastic element 24.

Rotational axes 31 c and 32 c are provided protruding from the bottomsurface of the lower chamber 31 and the top surface of the upper chamber32. This lower chamber 31 and upper chamber 32 are connected to arotational mechanism and rotated thereby as an integral unit.

Further, an air expelling outlet 27 a of the decompressing means 27 isopened at a position more inward than the flange portion 31 b in theradial direction, and more outer than the master medium 23 in the radialdirection, in the upper surface 31 a. An air channel 27 b connected tothis air expelling outlet 27 a is formed within the lower chamber 31,and leads to the exterior through the rotational axis portion 31 c,where it connects to a vacuum pump (not shown). By the expulsion of airby this decompressing means 27, the hermetically sealed space formed bythe upper chamber 32 and the lower chamber 31 can be controlled to apredetermined degree of vacuum of 50-100 Pa.

As shown in FIG. 3, the pressing means 26 is provided with apressurizing cylinder 34, and the distal end of the push rod 35 thereofapplies a predetermined pressure load to the upper chamber 32 of theconjoining apparatus 25. Note that because the conjoining apparatus 25is rotated while in the state in which pressure is being appliedthereto, the rotational axis portion 32 c of the upper chamber portion32 is provided with a receiving member 36 so as to facilitate theoperational effect of the applied pressure. The control of the degree ofvacuum pressure is made independent and is controlled to the optimalvalue so that the pressure from this pressure applying means 26 producesa resulting conjoinment pressure between the master medium 23 and thesalve medium 22 of 0.01-49N/cm² (1-5000 gf/cm²).

When a magnetic transfer is to be performed, an initial magnetization ofthe slave medium 22 is performed to magnetize the slave medium 22 in theplanar track direction for cases in which planar recording is to beperformed, and in the perpendicular direction for cases in which aperpendicular recording is to be performed. This slave medium 22 is thenconjoined with the master medium 23, and a transfer magnetic field isapplied in the direction substantially the opposite of that in which theinitial magnetization has been performed, or in the perpendiculardirection to perform the magnetic transfer.

A disk shaped recording medium such as a hard disk or a flexible diskhaving a magnetic recording portion (a magnetic layer) formed on one orboth surfaces thereof is employed as the slave medium 22. The magneticrecording portion consists of a magnetic recording layer that has beencoated onto the surface thereof, or a magnetic recording layer of thinmetallic film formed on the surface thereof.

A disk shaped medium formed of a hard material is employed as the mastermedium 23. This master medium 23 comprises a pliable magnetic layer thathas been coated over a micro uneven pattern formed on the surface of asubstrate; this surface becomes the transfer data bearing surface onwhich the transfer pattern that is to be brought into close contact withthe recording surface of the slave medium 22 has been formed. The faceof the master medium 23 opposite this transfer data bearing face is thesurface which is supported by vacuum adsorption on the lower chamber 31.

A synthetic resin, a ceramic material, an alloy, aluminum, glass,quartz, silicon, nickel, or the like is used to form the substrate ofthe master medium 23. The uneven pattern can be formed by use of astamping method or the like. The pliable magnetic layer is formed of amagnetic material by use of a vacuum layer forming means such as avacuum deposition method, a sputtering method, an ion plating method, orby a metal plating method, etc. A substantially identical type of mastermedium is used in both planar recording and perpendicular recording.

The elastic element 24 is formed of an elastic material in a disk shape,is supported on the upper chamber 32, and connects to and pressesagainst the back surface (upper surface) of the slave medium 22. As tothe elastic material used to form the elastic element 24, a siliconrubber, a polyurethane rubber, a fluorine rubber, 1,3-butadiene rubber,Teflon (registered trademark) rubber, viton rubber or other commonrubber, or a foam resin such as sponge rubber or the like can be usedtherefor.

For cases in which planar recording is to be performed, the magneticfield applying apparatus 28 for applying an initial magnetic field and atransfer magnetic field comprises, for example, a ring shapedelectromagnetic head disposed on both the upper and lower sides of theconjoined body provided with a core 38, which has a gap 37 extending inthe radial direction of the slave medium 22, around which a coil 39 hasbeen wound, and applies a transfer magnetic field, which is generated inthe direction parallel to the track direction, in the same directionfrom both the upper and lower sides of the conjoined body. Theconjoining apparatus 25 is rotated and the transfer magnetic field isapplied across the entire surface of the slave medium 22 and the mastermedium 23. The magnetic field applying means 28 can also be provided soas to be rotatable. The magnetic field applying means 28 can also bedisposed on only one side of the conjoining apparatus 25, or can be apermanent magnet apparatus disposed on one or both sides of theconjoining apparatus 25.

Further, for cases in which a perpendicular recording is to beperformed, the magnetic field applying apparatus 28 compriseselectromagnets or permanent magnets of different polarities disposed inthe upper and lower sides of the conjoining apparatus 25, respectively,wherein the transfer magnetic field is generated in the perpendiculardirection and applied. If the magnetic field applying apparatus 28 is ofthe type that applies a magnetic field to only a portion of the surface,the conjoining apparatus 5 or the magnetic field is moved to perform themagnetic transfer across the entirety of the surface.

The magnetic transfer apparatus 20 is an apparatus for performing amagnetic transfer from the same master medium 23 to a plurality of slavemediums 22: first, the positions of the master medium 23 and the elasticelement 24 are matched and supported in the lower chamber 31 and theupper chamber 32, respectively; then, while the upper chamber 32 and thelower chamber 31 are in the open state, that is, the state in whichthere is a separation therebetween, a slave medium 22, which has beensubjected to an initial magnetization in the planar direction or in theperpendicular direction in advance, is positioned wherein the centerposition hereof is matched and set; after which the pressing means 26 isdriven and the upper chamber 32 is moved toward the lower chamber 31.

Then, the seal 33 of the upper chamber 32 slidably contacts the innercircumference surface of the flange portion 31 b of the flange portion31, whereby the space in the interior between the chambers 31 and 32holding the master medium 23 and the slave medium 22 is hermeticallysealed. Before the slave medium 22 and the master medium 23 are in thepressurized state, the decompressing means 27 expels air from thehermetically sealed space so as to depressurize said space, and after apredetermined degree of vacuum has been obtained in the interior of saidhermetically sealed space, the upper chamber is further lowered towardsthe lower chamber. Pressure is applied by the pressing means 26, theback surface of the slave medium 22 is pressed against by the elasticelement 24, and the slave medium 22 and the master medium 23 areconjoined under a predetermined conjoining pressure.

Then, the upper and lower magnetic field applying apparatuses 28 aremade to approach the upper and lower faces of the conjoining means 25,and a transfer magnetic field is applied, while the conjoining apparatus25 is being rotated, in the direction substantially the opposite of thatin which the initial magnetization was applied, whereby the magneticpattern corresponding to the transfer pattern of the master medium 23 istransferred and recorded on the magnetic recording portion of the slavemedium 22.

The transfer magnetic field applied when the magnetic transfer isperformed is absorbed by the pattern of the protrusion portions formedby the pliable magnetic body of the transfer pattern on master medium 3conjoined with slave medium 22, and as a result: in the case of planarrecording, the initial magnetization of this portion is not inverted,whereas the initial magnetization of the other portions is inverted; inthe case of perpendicular recording, the initial magnetization of thisportion is inverted, whereas the initial magnetization of the otherportions is not inverted, and the magnetic data corresponding to thetransfer pattern formed on the master medium 23 is transferred andrecorded on the slave medium 22.

According to the current embodiment: because the lower chamber 31 andthe upper chamber 32 are first brought together and the interior portiontherebetween hermetically sealed, and the interior portion thereof isthen decompressed to a predetermined degree of vacuum and the remainingair expelled therefrom while in the hermetically sealed state, afterwhich a predetermined pressure is applied independently so as to conjointhe master medium 23 and the slave medium 22, the conjoinment of themaster and slave mediums can be improved by conjoining said master andslave medium at an optimal degree of vacuum and pressure, whereby thetransfer deficiencies accompanying contact deficiencies can be preventedand a favorable magnetic transfer can be performed.

Next, yet another embodiment according of the present invention will beexplained. FIG. 5 is a perspective view of the main portion of amagnetic transfer apparatus in the transfer state according to anembodiment of the present invention. FIG. 6 is an exploded perspectiveview of a conjoining apparatus, and FIG. 7 is a plan view of an elasticpressing member and a master medium according an embodiment of thepresent invention. Note that each of said drawings is a model drawing;the thickness and other actual dimensions of the portions shown thereinare of a different ratio.

The magnetic transfer apparatus 40 shown in FIG. 5 comprises: a lowerpressure contact member 48 and an upper pressure contact member 49;wherein a master medium 43 and a slave medium 42 and an elastic pressingmember 44 are disposed in the interior portions of the lower pressurecontact member 48 and the upper pressure contact member 49 as shown inFIG. 6; a conjoining means 45 provided for matching the center positionsthereof and conjoining said master medium 49 and slave medium 48; apressure applying apparatus 46 for applying pressure to the conjoiningapparatus 45; and a magnetic field applying apparatus 47 for applying atransfer magnetic field while rotating the conjoining apparatus 45.

When a magnetic transfer is to be performed, an initial magnetization ofthe slave medium 42 is performed in advance by applying an initialdirect current to magnetize the slave medium 42 in the planar trackdirection for cases in which planar recording is to be performed, and inthe perpendicular direction for cases in which a perpendicular recordingis to be performed. This slave medium 42 is then conjoined with themaster medium 43, and a transfer magnetic field is applied in thedirection substantially the opposite of that in which the initial directcurrent magnetization has been performed, or in the perpendiculardirection to perform the magnetic transfer.

A disk shaped recording medium such as a hard disk or a flexible diskhaving a magnetic recording portion (a magnetic layer) formed on one orboth surfaces thereof, and on which a central aperture 42 a has beenopened is employed as the slave medium 42. The magnetic recordingportion consists of a magnetic recording layer that has been coated ontothe surface thereof, or a magnetic recording layer of thin metallic filmformed on the surface thereof.

A disk shaped medium formed of a hard material on which a centralaperture 43 a has been opened is employed as the master medium 43. Thismaster medium 43 comprises a pliable magnetic layer that covers a microuneven pattern formed on the surface of a substrate; this surface is thetransfer data bearing surface 43 b on which the transfer pattern that isto be brought into close contact with the recording surface of the slavemedium 42 has been formed. The face of the master medium 43 oppositethis transfer data bearing face is the surface which is supported byvacuum adsorption on the lower pressure member 48.

A synthetic resin, a ceramic material, an alloy, aluminum, glass,quartz, silicon, nickel, or the like is used to form the substrate ofthe master medium 43. The uneven pattern can be formed by use of astamping method or the like. This pliable magnetic layer is formed of amagnetic material by use of a vacuum layer forming means such as avacuum deposition method, a sputtering method, an ion plating method, orby a metal plating method, etc. A substantially identical type of mastermedium 43 is used in both planar recording and perpendicular recording.

For the case in which the transfer data is a servo signal, a servopattern P (a transfer pattern) is formed in narrow regions extendingfrom the center at equal intervals in a substantially radial pattern(slightly curved in the drawing), as shown in FIG. 7B. The portions ofthis servo pattern P are the portions that are required to be broughtinto contact with the slave medium 42, and the magnetic patterncorresponding to the servo pattern P is transferred and recorded ontothe slave medium 42 by the magnetic transfer.

The elastic pressing member 44 is formed of an elastic material in adisk shape, is supported on the upper pressure contact member 49, andconnects to and presses against the back surface (upper surface) of theslave medium 42. The form of the pressing surface 44 a of the elasticpressing member 44 that is to be brought into contact with the backsurface of the slave medium 42, as shown in FIG. 7A, is provided withdepression and protrusion portions for pressing mainly against theportions that correspond to the servo pattern P of the master medium 43.

The pressing surface 44 a comprises an inner ring portion 50 on theinner circumference thereof, an outer ring portion 51 on the outercircumference thereof, and a plurality of radial portions 42corresponding to the servo pattern P of the master medium 43 joining theinner ring portion 50 and the outer ring portion 51, which is formed asthe pressing protrusion portion that contacts the slave medium 42. Theother portions thereof are formed as depression portions 53 (which canbe devoid of substance and open clear through to the back surface), anddo not come into contact with the slave medium 42.

The elastic material used to form the elastic pressing member 44 mustexhibit a degree of elasticity wherein the pressing surface area doesnot increase excessively when pressure is applied. More specifically, asilicon rubber, a polyurethane rubber, a fluorine rubber, 1,3-butadienerubber, Teflon (registered trademark) rubber, viton rubber or othercommon rubbers, or a foam resin such as sponge rubber or the like can beused therefor.

The lower pressure contact member 48 of the conjoining apparatus 45 isprovided with a circular adsorption surface 48 a corresponding to thesize of the master medium 43; the surface thereof has been finished tobe flat. This adsorption surface 48 a is a surface on which asubstantially uniformly dispersed plurality of suction pores have beenopened (a porous surface can also be used). Although not shown in thedrawing, these suction pores are connected by a suction channel leadingfrom the interior to the exterior of the lower pressure contact member48 to a vacuum suction pump that provides the suction force; the bottomsurface of the master medium 43 brought into close contact with theadsorption surface 48 a is vacuum adsorbed, and the flatness of saidmaster medium 43 is favorably corrected along the surface of theadsorption surface 48 a. The upper pressure contact member 49 isprovided with a support surface 49 a for holding the elastic pressingmember 44.

The outer form of the lower pressure contact member 48 and the upperpressure contact member 49 is disk shaped, and the upper pressurecontact member 49 is movable in the axial direction; wherein, the upperpressure contact member 49 is moved in the separation or contactdirection by the pressure applying apparatus 46, and the lower pressurecontact means 48 and the upper pressure contact means 49 are broughtinto pressurized contact at a predetermined pressure. The lower pressurecontact member 48 and the upper pressure contact member 49 are providedwith a flange portion 48 b and a flange portion 49 b on the respectiveouter circumferences thereof, and when the closing operation is to beperformed, the flange portion 48 b and a flange portion 49 b of thelower pressure contact member 48 and the upper pressure contact member49 abut each other, whereby the interior portion thereof is maintainedin a hermetically sealed state. A pin 48 c for coupling with the centralapertures 43 a and 42 a of the master medium 43 and the slave medium 42and determining the positions thereof, respectively, is provided at thecenter portion of the lower pressure contact member 48. The position ofthe radial portions 52 of the elastic pressing member 44 is matched tothe position of the servo pattern P of the master medium 43 andsupported in the matched position state by use of a positioningmechanism (not shown) that is provided on the support surface 49 a ofthe upper pressure member 49. Further, the lower pressure member 48 andthe upper pressure member 49 are connected to a rotational mechanism(not shown) and rotated thereby as an integral unit.

As shown in FIG. 5, the pressure applying means 46 is provided with apressurizing cylinder 54, and the distal end of the push rod 55 thereofapplies a predetermined pushing pressure load to the upper pressuremember 49 of the conjoining apparatus 45. The pushing force is set,based on the contact surface area, so that the pushing force from thispressure applying means 46 results in a conjoinment pressure between themaster medium 43 and the salve medium 42 in the vicinity of the servopattern P is of the optimal value of 0.01-50 N/cm² (1-5.0 kg/cm²). Notethat because the conjoining apparatus 45 is rotated while in thepressurized state, the center axis portion 49 c of the upper chamberpressure member 49 is provided with a receiving member 56 so as tofacilitate the operational effect of the applied pressure.

For cases in which planar recording is to be performed, the magneticfield applying apparatus 47 for applying an initial magnetizationmagnetic field and a transfer magnetic field comprises, for example, aring shaped electromagnetic head disposed on both the upper and lowersides of the conjoined body and which is provided with a core 58, whichhas a gap 57 extending in the radial direction of the slave medium 42,around which a coil 59 has been wound, and applies a transfer magneticfield, which is generated in the direction parallel to the trackdirection, in the same direction from both the upper and lower sides ofthe conjoined body. The conjoining apparatus 45 is rotated and thetransfer magnetic field is applied across the entire surface of theslave medium 42 and the master medium 43. The magnetic field applyingmeans 47 can also be provided so as to be rotatable. The magnetic fieldapplying means 47 can also be disposed on only one side of theconjoining apparatus 45, or can be a permanent magnet apparatus disposedon one or both sides of the conjoining apparatus 45.

Further, for cases in which perpendicular recording is to be performed,the magnetic field applying apparatus 47 comprises electromagnets orpermanent magnets of different polarities disposed in the upper andlower sides of the conjoining apparatus 45, respectively, wherein thetransfer magnetic field is generated in the perpendicular direction andapplied. If the magnetic field applying apparatus 47 is of the type thatapplies a magnetic field to only a portion of the surface, theconjoining apparatus 45 or the magnetic field is moved to perform themagnetic transfer across the entirety of the surface.

The magnetic transfer apparatus 40 is an apparatus for performing amagnetic transfer from the same master medium 43 to a plurality of slavemediums 42: first, the center position of each of the master medium 43and the elastic pressing member 44 are matched to the that of the lowerpressure contact member 48 and the upper pressure contact member 49,respectively, then the pattern positions of each of the master medium 43and the elastic pressing member 44 are matched, and the master medium 43and the elastic pressing member 44 are held by the lower pressurecontact member 48 and the upper pressure contact member 49,respectively; then, while the lower pressure contact member 48 and theupper pressure contact member 49 are in the open state, that is, thestate in which there is a separation therebetween, a slave medium 42,which has been subjected to an initial magnetization in one of eitherthe planar direction or the perpendicular direction in advance, ispositioned wherein the center position thereof is matched and set; afterwhich the pressing means 46 is driven and the upper pressure member 49is moved toward the lower pressure member 48 to perform the closingoperation; the elastic pressing member 44 is brought into contact withthe back face of the slave medium 42, wherein the protrusion portion ofthe pushing surface 44 a thereof presses the slave medium mainly againstthe proximity of the servo pattern P to conjoin the master medium 43 andthe slave medium 42. Then, the upper and lower magnetic field applyingapparatuses 47 are made to approach with the upper and lower faces ofthe conjoining means 45, and a transfer magnetic field is applied, whilethe conjoining apparatus 45 is being rotated, in the directionsubstantially the opposite of that in which the initial magnetizationcurrent was applied, whereby the magnetic pattern corresponding to thetransfer pattern of the master medium 43 is transferred and recorded onthe magnetic recording portion of the slave medium 42.

The transfer magnetic field applied when the magnetic transfer isperformed is absorbed by the pattern of the protrusion portions formedby the pliable magnetic body of the transfer pattern on the mastermedium 43 and conjoined with the slave medium 42, and as a result: inthe case of planar recording, the initial magnetization of this portionis not inverted, whereas the initial magnetization of the other portionsis inverted; in the case of perpendicular recording, the initialmagnetization of this portion is inverted, whereas the initialmagnetization of the other portions is not inverted, and the magneticdata corresponding to the transfer pattern formed on the master medium43 is transferred and recorded on the slave medium 42.

According to the current embodiment: because the elastic pressing member44 provided with the pushing surface 44 a, which is formed of thedepression portion and the protrusion portion, presses against the backsurface of the slave medium 42 at mainly the transfer pattern portion ofthe master medium 43 when the master medium 43 and the slave medium 42are to be conjoined, the contact at the pattern portion required for theconjoinment is improved, whereby the transfer deficiencies accompanyingcontact deficiencies can be prevented and a favorable magnetic transfercan be performed, and the overall pushing pressure can be lowered,enabling the apparatus to be made more compact.

Next, still yet another embodiment according of the present inventionwill be explained. FIG. 8 is a perspective view of the main portion of amagnetic transfer apparatus in the transfer state according to anembodiment of the present invention. FIG. 9 is an exploded perspectiveview of a holder.

The magnetic transfer apparatus 60 shown in FIGS. 8 and 9 is anapparatus for performing a planar recording type magnetic transfer onboth recording surfaces of a slave medium 62 concurrently: disk shapedmaster mediums 63 and 64 are conjoined to the upper and lower surfacesof a slave medium 62 within a holder 61; said holder 61 is rotated andwhile said holder 61 is rotating a transfer magnetic field is appliedthereto by a magnetic field applying apparatus 65 (an electromagneticapparatus) disposed on the upper and lower sides of said holder 61 toconcurrently magnetically transfer and record the data borne on themaster mediums 63 and 64 to both recording surfaces of the slave medium62.

The holder 61 comprises a lower holder 68 and upper holder 69 bothhaving cylindrical structures; wherein a lower master medium 63 fortransferring data such as a servo signal or the like to the lower siderecording surface of the slave medium 62, and an upper master medium 64for transferring data such as a servo signal or the like to the upperside recording surface of the slave medium 62 are exchangeably housedtherein. The lower holder 68 is provided with a lower adsorption member66 for adsorbing the lower master medium 63 and correcting the flatnessthereof, and the upper holder 69 is provided with an upper adsorptionmember 67 (of the same configuration as the lower suction member 66) foradsorbing the upper master medium 64 and correcting the flatnessthereof. The center positions of the respective upper master medium 64and the lower master medium 63 are matched with the center position ofthe slave medium 62, pressure contacted to both sides of said slavemedium 2 while maintained in the position-matched state, and opposinglyconjoined with the upper and lower surfaces of said slave medium 62,respectively. Here, “opposingly conjoined” refers to either theconjoined state in which the surfaces of the master mediums 63, 64 andthe slave medium 62 are in contact, or the state in which said surfacesare facing one another while a small gap exists therebetween.

One or both of the lower holder 68 and the upper holder 69 are providedso as to be movable in the axial direction thereof, and are opened andclosed by the operation of an opening and closing mechanism (not shown).Further, the holder 61 is provided with a vacuum suction means (notshown) for vacuum suctioning the air contained within the interior spaceformed by the slidable contact of the lower holder 68 and the upperholder 69, whereby a depressurized state is produced in the interiorportion thereof, and contact force is obtained between the slave medium62 and the upper and lower master mediums 63 and 64.

The slave medium 62 shown in the drawing is a hard disk in which acentral aperture 62 a has been opened at the center portion thereof forpositioning the slave medium 62 on a rotation support axis of a driveapparatus, and has a recording surface formed of a magnetic layer onboth surfaces of a disk shaped base.

Further, a center pin 68 b for determining the position of the slavemedium 62, taking the central aperture 62 a as the standard ofreference, is provided at the center of the lower holder 68. Thepositioning of the lower master medium 63 is also performed by thiscenter pin 68 b; a positioning central aperture 63 a for insertion ofthe center pin 68 b is opened at the center portion of the lower mastermedium 63. The positioning of the upper master medium 64 in the upperholder 69 is performed by inserting a center pin (not shown) of the sametype as the center pin 68 b, that is provided at the center position ofthe upper holder 69 in a central aperture 64 a provided on the uppermaster medium 64. Further, a mechanism that determines the positions ofthe lower holder 68 and the upper holder 69 is provided, which serves tomatch the center positions of the lower master medium 63 and the uppermaster medium 64.

According to the position matching performed by use of the center pin 68b provided on the holder 68 described above, as shown in FIG. 10, theamount of eccentricity c between the center position 63 c of the lowermaster medium 63 and the center position 62 c of the slave medium 62 isset so as to be less than or equal to 100 um. The amount of eccentricitybetween the center positions of the upper master medium 64 and the slavemedium 62 are also set in the same manner so as to be less than or equalto 100 um.

Further, it is desirable that the amount of eccentricity between thecenter positions of the patterns formed on the master mediums 63 and 64,respectively, and the rotational center position of the slave medium 62be set so as to be less than or equal to 50 um.

When a magnetic transfer is to be performed, the slave medium 62 issubjected to an initial direct current magnetization in the planar trackdirection, in the case of planar recording, or in the perpendiculardirection, in the case of perpendicular recording, in advance. Whenperforming the magnetic transfer on this conjoined slave medium 62 andmaster mediums 63 and 64, the transfer magnetic field is applied in thetrack direction substantially the opposite of the direction in which theinitial magnetization has been performed, or in the perpendiculardirection.

The lower master medium 63 and the upper master medium 64 are formed asring shaped disks provided with a transfer data bearing surface, whichcomprises a pattern formed of a magnetic body, on one surface thereof,which is to be conjoined with the recording surface of the slave medium62; the surfaces of the master mediums 63 and 64 opposite these databearing surfaces are vacuum adsorbed by a lower adsorption member 66 andan upper adsorption member 67, respectively.

The master mediums 63, 64 comprise a pliable magnetic layer that coversa micro uneven pattern formed on the surface of a substrate; thissurface is the transfer data bearing surface. A synthetic resin, aceramic material, an alloy, aluminum, glass, quartz, silicon, nickel, orthe like is used to form the substrate of the master mediums 63, 64. Theuneven pattern can be formed by use of a stamping method or the like.This pliable magnetic layer is formed of a magnetic material by use of avacuum layer forming means such as a vacuum deposition method, asputtering method, an ion platting method, or by a metal plating method,etc. A substantially identical type of master medium 43 is used in bothplanar recording and perpendicular recording.

The lower adsorption member 66 (the same is true of the upper suctionmember 67) is provided as a disk having a size corresponding to that ofthe master medium 63, and the surface thereof is formed as an adsorptionsurface 66 a finished to a flatness having an center line averagesurface roughness Ra of 0.0-0.1 um. Approximately 25-100 suction pores66 b having diameters of approximately 2 mm or less are opened on thissuction surface 66 a, and dispersed substantially uniformly thereacross.Although not shown in the drawing, these suction pores 66 b areconnected by a suction channel leading from the interior to the exteriorof the holder 68 to a vacuum suction pump that provides the suctionforce; the back surface of the master medium 63 brought into closecontact with the adsorption surface 66 a is adsorbed, and the flatnessof said master medium 63 is corrected along the adsorption surface 66 a.

The lower holder 68 and the upper holder 69 are disk shaped: an upwardprotruding flange portion 68 a is provided on the outer circumference ofthe lower holder 68, and a downward protruding flange portion 69 a isprovided on the outer circumference of the upper holder 69. Though thedetails are not shown in the drawing, the diameter of the outercircumference surface of the flange portion 69 a of the upper holder 69is smaller than the diameter of the inner circumference surface of theflange portion 68 a of the lower holder 68, and the flange portion 69 aof the upper holder 69 is provided so as to be insertable into the innercircumferential side of the flange portion 68 a of the lower holder 68(the size relation between the respective flange portions can bereversed). Further, a seal element (not shown), which is an O-ring, isinstalled around the outer circumference of the flange portion 69 a ofthe upper holder 69, and when the upper holder 69 is moved toward thelower holder 68, this seal element slidably contacts the innercircumference surface of the flange portion 68 a of the lower holder 68,serving to seal off the surfaces in the direction substantially parallelto that of the separation and contact direction (the axial direction),thereby hermetically sealing the space within the interior of both thelower holder 68 an the upper holder 69. The seal element can also beinstalled on the lower holder 68.

The holder 61 comprises a lower holder 68 and an upper holder 69 whichare provided as a cylindrical structures which are movable in theseparation and contact direction in a state in which the interior spacebetween the lower holder 68 and the upper holder 60 are sealed; wherein,even if the thickness of the slave medium 62, and the master mediums 63,64 changes and the height of the conjoined body formed thereby changes,the sealed state is ensured. The lower holder 68 and the upper holder 69are connected to a rotational mechanism (not shown) and rotated therebyas an integral unit.

Further, a suction opening of the vacuum suction means is provided onthe inner surface of the holder 61, and opens onto the interior spacethereof. An air channel connected to this air suction opening is formedwithin the lower holder 68 or the upper holder 69, and leads to theoutside, where it connects to a vacuum pump. By the vacuum suction ofair by this vacuum suction means, the vacuum in the hermetically sealedspace formed within the holder 61 can be controlled to a predetermineddegree.

When the magnetic transfer is to be performed: the upper holder 69 andthe lower holder 68 are moved by the pressure accompanying the vacuumsuction so as to approach each other; the data bearing faces of thelower master medium 63 and the upper master medium 64 are opposinglyconjoined with the respective recording surfaces of the slave medium 62;the magnetic field applying apparatus 65 applies a transfer magneticfield to the conjoined body formed by the master mediums 63, 64 and theslave medium 62 to magnetically transfer and record the data such as aservo signal or the like from the data bearing surfaces of therespective master mediums 63, 64 to the respective recording surfaces ofthe slave medium 62. Note that as to the method of applying theconjoining force, in addition to the vacuum suction method describedabove, or in place thereof, it is possible to employ a method whereinexternal mechanical pressure is applied.

For cases in which planar recording is to be performed, the magneticfield applying apparatus 65 for applying an initial magnetic field and atransfer magnetic field comprises, for example, a ring shapedelectromagnetic head disposed on both the upper and lower sides of theconjoined body provided with a core, which has a gap extending in theradial direction of the slave medium 62, around which a coil has beenwound, and applies a transfer magnetic field, which is generated in thedirection parallel to the track direction, in the same direction fromboth the upper and lower sides of the conjoined body. The holder 61 isrotated and the transfer magnetic field is applied across the entiresurface of the slave medium 62 and the master mediums 63, 64. Themagnetic field applying means 65 can also be provided so as to berotatable. The magnetic field applying means 65 can also be disposed ononly one side of the holder 61, or can be a permanent magnet apparatusdisposed on one or both sides of the of the holder 61.

Further, for cases in which a perpendicular recording is to beperformed, the magnetic field applying apparatus 65 compriseselectromagnets or permanent magnets of different polarities disposed onthe upper and lower sides of the holder 61, respectively, wherein thetransfer magnetic field is generated in the perpendicular direction andapplied. If the magnetic field applying apparatus 28 is of the type thatapplies a magnetic field to only a portion of the surface, the holder 61or the magnetic field is moved to perform the magnetic transfer acrossthe entirety of the surface.

Next, the magnetic transfer process performed by a magnetic transferapparatus such as the magnetic transfer apparatus 60 described abovewill be explained. According to this magnetic transfer apparatus 60, amagnetic transfer is repeatedly performed from the same master mediums63, 64 to a plurality of slave mediums 62: first, the center positionsof the lower adsorption member 66 of the lower holder 68 and the mastermedium 63, and the upper adsorption member 67 of the upper holder 69 andthe master medium 64 are matched, respectively, and the master mediums63, 64 are adsorbed by the lower adsorption member 67 and the upperadsorption member 67, respectively.

Then, while the upper holder 69 and the lower holder 68 are in the openstate, that is, the state in which there is a separation therebetween, aslave medium 62, which has been subjected to an initial magnetization inthe planar direction or in the perpendicular direction in advance, ispositioned wherein the center position thereof is matched and set; afterwhich the upper holder 69 is moved to approach the lower holder 68thereby performing the closing operation; by the slidably contactedengagement between the flange portion 68 a of the lower holder 68 andthe flange portion 69 a of the upper holder 9, the space in the interiorof the holder 61 is hermetically sealed. The vacuum suction means expelsair from the interior space of the holder 61 so as to depressurize saidspace, and to obtain a predetermined degree of vacuum. In this manner,by the external force (atmospheric pressure) that operates incorrespondence to the degree of vacuum on the upper holder 69,conjoining force is added so as to move the upper holder 69 towards thelower holder 68 and sandwich the slave medium 62 between the upper andlower master mediums 63, 64 to conjoin said slave medium 62 and saidmaster mediums 63, 64 uniformly under a predetermined conjoining force.

Then, the upper and lower magnetic field applying apparatuses 65 aremade to approach the upper and lower faces of the holder 61, said holder61 is rotated and a transfer magnetic field is applied, while saidholder 61 is rotating, in the direction substantially the opposite ofthat in which the initial magnetization current was applied. Thetransfer magnetic field applied when the magnetic transfer is performedis absorbed by the pattern of the protrusion portions formed by thepliable magnetic body of the transfer pattern on the master mediums 63,64 and conjoined with the respective recording surfaces of the slavemedium 2, and as a result: in the case of planar recording, the initialmagnetization of this portion is not inverted, whereas the initialmagnetization of the other portions is inverted; in the case ofperpendicular recording, the initial magnetization of this portion isinverted, whereas the initial magnetization of the other portions is notinverted, and the magnetic pattern corresponding to the transfer patternof the master mediums 63, 64 is transferred and recorded on therespective magnetic recording portions of the slave medium 62.

According to the current embodiment, a holder 61 configured so as toconjoin a master medium 63 and a master medium 64 are opposinglyconjoined with the opposite recording surfaces of a slave medium 62 isprovided; wherein, by setting the center positions of the master mediums63, 64, and the slave medium 62 so that the amount of eccentricitybetween said respective center positions is less than or equal to 100um, contact across the entirety of the respective surfaces of the mastermediums 63, 64 and the slave medium 62, wherein the contact force at thecontact regions of said master mediums 63, 64 and the slave medium 62 isuniform, can be realized, the application of localized contact force canbe prevented, and the occurrence of damage to the edges due to contacton only one side can be prevented. Further, by accurately matching thecenter positions of the master mediums 63, 64 and slave medium 62, atransfer signal having a desired performance level can be recorded.

Hereinafter, yet another embodiment according of the present inventionwill be explained. FIG. 11 is a perspective view of the main portion ofthe transfer state of a magnetic transfer apparatus, which implementsthe magnetic transfer method according to an embodiment of the presentinvention, in the transfer state. FIG. 12 is a cross-sectional view of amagnetic transfer apparatus in the conjoined state. FIG. 13 is aschematic drawing of a measuring microscope for use in adjusting theposition of the master medium. FIGS. 14 and 15 are plan views of theposition adjustment process for a master medium. FIG. 16 is across-sectional drawing of the main part of a magnetic transferapparatus according to the current embodiment in the state before closecontact.

The magnetic transfer apparatus 70 shown in FIG. 11 is an apparatus forpressure conjoining, by use of a pressure applying means (a pressmechanism), which is not shown in the drawing, the data bearing surfaceof a disk shaped master medium 73 on which a pattern corresponding tothe transfer data such as a servo signal has been formed, and therecording surface of a disk shaped slave medium 62 formed of a magneticrecording medium for receiving the transfer from the master medium,between a first base plate 76 (a rotational base plate) and a secondbase plate 77 (a pressing member) as shown in FIG. 12 to form aconjoined body, and applying a transfer magnetic field thereto by use ofa magnetic field applying apparatus 75 disposed on the upper and lowersides of said conjoined body. The master medium 73 is disposed on theupper portion of the first (lower) base plate 76, and the slave medium72 is disposed on the lower portion of the second base plate 77, abovethe master medium 73.

The first (lower) base plate 76 is provided with a slave support axis 94for positioning the central aperture 72 a of the slave medium 72 at thecenter position of the upper portion of abase member 93, and a mastersupporting member 95 for supporting the master medium 73 is provided onthe outer circumference of this slave support axis 94. The mastersupporting member 95 is provided so that the position thereof isadjustable in the x, y axes relative to the slave support axis 94.

The position of the master supporting member 95, on which the mastermedium 73 is being supported, is adjusted so that the center position ofthe pattern 86 (refer to FIG. 14) formed on said master medium 73 ismatched to the center position of the slave support axis 94 and fixed inthe matched position as described below; wherein the matching of thepositions of said master medium 73 and the slave medium 72 suppliedabove said master medium 73 are is performed by coupling the centralaperture 72 a of said slave medium 72 with the slave support axis 94.

The slave medium 72 is a disk shaped recording medium such as a harddisk, on which a magnetic recording layer has been formed on bothsurfaces thereof. The slave support axis for supporting this slavemedium 72 is formed as a protrusion, and the outer diameter thereof isformed so as to be of substantially the same diameter as the centralaperture 72 a of the slave medium 72; whereby upon the positioning ofthe central aperture 72 a of the slave medium onto the slave axis 94,the center position of said slave medium 72 is supported so as to bematched to the standard centering position of the slave support axis 94.The slave support axis 94 is formed so that the amount thereofprotruding above the upper surface of the master medium 73 is less thanthe thickness of the slave medium 72 (for cases in which a depressionportion is formed at the center position of the second base plate 77,the height may be taller).

Meanwhile, the master medium 73 is formed as a ring shape having aninner aperture of which the diameter thereof is larger than the outerdiameter of the slave support axis 94, and although it is not shown indetail, the master medium 73 is provided with a transfer data bearingsurface on one surface thereof (the upper surface in the drawing), whichconsists of a micro uneven pattern 86 formed as a concentric to the ringshaped track, and the face opposite thereto (the bottom face in thedrawing) is supported on the upper surface of the master supportingmember 95.

The base member 93 of the first base plate 76 is formed in a disk shape,and the slave support axis 94 is provided upright at the center portionof the upper surface thereof so as to pass through the lower and uppersurfaces of the master supporting member 95. The master supportingmember 95 is disposed on the outer circumference of the base member 93of the first base plate 76, and comprises, for example, guides 96 in twoperpendicularly intersecting directions that are provided with an xdirection movement portion and a y direction movement portion stackedone upon the other so as to be movable in the x and y direction; whereinthe amount of movement in each of the two directions is adjustable byuse of an adjustment mechanism (not shown), and each of said x directionmovement portion and y direction movement portion can be fixed inposition so as to be immobile after the adjustment has been performed.The master medium 73 is supported by suction or the like on the uppersurface of this master supporting member 95: for example, a plurality ofsuction pores is opened on the upper surface of the master supportmember 95, and the master medium 73 loaded thereon is fixed in place byair suction.

The first base plate 76 is provided so as to be removable from thetransfer position; the first base plate 76 is transferred to themeasuring microscope 80 shown in FIG. 13, and the center position of thepattern 86 formed on the master medium 73 is adjusted so as to bematched with the center position of the slave support axis 94. Note thatthe first base plate 76 is rotated by a rotational driving means (notshown).

The second base plate 77 is formed as a disk the same as the first baseplate 76; this second base plate 77 constitutes the pressure applyingmeans, and is provided so as to be movable in the vertical direction bya rising and falling mechanism (not shown), wherein, the pressure from acylinder or the like is applied by a mechanism (not shown).

The measuring microscope 80 shown in FIG. 13 comprises: a base 81; and asupport post 82 erected on said base 81 perpendicular to the uppersurface thereof; and an observation portion 83 formed of an opticalsystem which is supported on said support post 82 and movable in thevertical direction. A stage 84, which is movable in the XY directions,is provided on the upper surface of the base 81; said stage 84 is movedin the x direction and the y direction by the operation of a handle 85.Although not shown in the drawing, the stage 84 is provided with amovement amount detecting means for detecting the amount of movementthereof; a computing portion (a personal computer) performs variouscomputations based on a detection by the detecting means; and a displayportion for displaying coordinates and the like.

The first base plate 76 is loaded onto the stage 84 and can be movedwhile being observed by the observation portion; a plurality ofreference points 86 a (refer to FIG. 14) or a mark 88 (refer to FIG. 17)are plotted as the base points in the field of vision, a nearly circularshape is described and computations can be performed to derive thecenter position thereof; the coordinates of said center position arethen displayed on the display portion. Further, the center position ofthe slave support axis 94 is measured in the same manner, and thecoordinates thereof are displayed on the display portion. Note that itis preferable, when position matching is performed, to display theamount of deviation between the coordinates of the two center positions.

The positioning of the master medium 73 by use of the measuringmicroscope 80 will be explained based on FIGS. 14 and 15. First, asshown in FIG. 14, in the state in which the master medium 73 has beenloaded onto the master supporting member 95 by a manual operation or thelike, the center position of the pattern 86 of the master medium 73 ismisaligned with respect to the center position of the slave support axis94 (in FIG. 14, displaced downward and to the left), and is in aneccentric state. Then, the first base plate 76 is loaded onto the stage84 of the measuring microscope 80, and by observing with the observationportion 83 and operating the stage 84, the center position of the slavesupport axis 94 is obtained, and the center position of the pattern 86of the master medium 73 is obtained in the same manner by, for example,plotting the plurality of starting point signals occurring for theplurality of frames on the outer circumferential track as referencepoints 86 a and performing the computations to obtain the centerposition of said pattern 86; the positions of both the pattern 86 of themaster medium 73 and the slave support 94 are matched by moving themaster supporting member 95 in the x and y directions (upward and to theright in the drawing) to adjust the position thereof, wherein byrepeating this position adjusting operation, said both center positionscan be matched, as shown in FIG. 15, and the master supporting member 95can then be fixed in the center position matched state.

Note that instead of measuring a portion of the pattern 86 as referencepoints 86 a, as shown in FIG. 17, a position matching mark 88 can beformed together with the pattern 86, and this mark 88 can be measured byuse of the measuring microscope 80 and the center position of thepattern 86 obtained. The mark 88 can be, for example, a plurality ofpoints along a circle on the outer portion of the pattern 86, concentrictherewith.

The magnetic field applying means 75 shown in FIG. 11 comprises:electromagnetic apparatuses 89, 89 disposed on both upper and lowersides, which are each formed of a core 91 having a gap 90 extending inthe radial direction of the slave medium 72 and the master medium 73,around which a coil 92 has been wound; and applies a transfer magneticfield, which is generated in the direction parallel to the trackdirection, in the same direction from both the upper and lower sides.Note that the magnetic field applying means 75 a can also be configuredof permanent magnet apparatuses instead of electromagnetic apparatuses,and can also be disposed on only one side.

When the magnetic transfer field is to be applied, the slave medium 72and the master medium 73 are rotated as an integral unit, that is, as aconjoined body, and the magnetic field applying means 75 applies atransfer magnetic field thereto while said conjoined body is rotating;whereby the transfer data of the master medium 73 is transferred andrecorded onto the entire track circumference of the slave medium 72.Alternatively, the magnetic field applying means 75 can be provided soas to be rotatable. Further, in order to permit the opening and closingoperation of the first base plate 76 and the second base plate 77, themagnetic field applying means 75 can be provided so that theelectromagnetic apparatus 89 moves away therefrom to a standby position.

Next the operation of the magnetic transfer apparatus 70 describedabove, that is, the magnetic transfer method will be explained. First,as shown in FIG. 16, the second base plate 77 is raised and maintainedin the preconjoinment state, and after the center position of thepattern 86 of the master medium 73 which is supported in the mastersupporting member 95 of the first base plate 76, has been matched withthe center position of the slave support axis in advance in the manneras described above, the slave medium 72 is conveyed onto said mastermedium 73, and the central aperture 72 a thereof is emplaced over theslave support axis 94 and the slave medium 72 is thereby loaded. Byperforming the position matching by use of this slave support member 94,the center position of the pattern 86 of the master medium 73 can bematched with the rotational center of the slave medium 72 with a highdegree of accuracy.

Then, the second base plate 77 is lowered by the pressure applyingmeans, whereby the pressing surface of the second base plate 77 isbought into contact with the upper surface of the slave medium 72, andthis slave medium 72 is pressed so that the lower surface thereof (themagnetic recording surface) is brought into close contact and conjoinedwith the upper surface (the data bearing surface) of the master medium73 at a predetermined pressure. Next, the both the upper and lowermagnetic field applying apparatuses 89, 89 are made to approach theconjoined body formed by the conjoined master medium 73 and slave medium72, and apply the transfer magnetic field thereto while the first baseplate 76 and the second base plate 77 are being rotated substantiallyone full rotation; whereby the magnetic pattern corresponding to thetransfer data borne on the master medium is transferred and recorded onthe recording surface of the slave medium 72.

After the magnetic transfer has been completed, the second base plate 77is raised thereby releasing the pressure, the slave medium 72 to whichthe transfer has been made is separated from the master medium 73, andremoved and conveyed. Then, in a separate process, the slave medium 72is inverted and again set onto the slave support axis 94, and theopposite surface thereof is conjoined with the master medium 73 and amagnetic transfer is performed in the same manner as described above.

Further, as shown in FIG. 18, the apparatus can be configured so as toperform the magnetic transfer on both recording surfaces of the slavemedium 72 concurrently. The lower-side first base plate 76, in the samemanner as described above, is provided with a slave support axis 94 forpositioning the central aperture 72 a of the slave medium 72 at thecenter position of the upper portion of a base member 93, and a mastersupporting member 95 for supporting the master medium 73 is provided onthe outer circumference of this slave support axis 94; wherein thecenter position of the pattern 86 formed on the master medium is matchedwith the center position of the slave support axis 94. A positioninghole 94 a is provided at the center position of the slave support axis94.

Meanwhile, the second base plate 77 is provided with: a positioning pin98 at the center position of the lower portion of the base 97 forinsertion into the positioning hole 94 a of the slave support axis 94; amaster supporting member 99 for supporting a master medium 74 on theouter circumferential area of this positioning pin 98; wherein thecenter position of the pattern 86 formed on the master medium 74 ismatched with the center position of the position matching pin 98 andfixed in place at said matched position.

Then, when the magnetic transfer is to be performed, the slave medium 72is conveyed onto said master medium 73 supported in the mastersupporting member 95 of the first base plate 76, and the centralaperture 72 a thereof is emplaced over the slave support axis 94 and theslave medium 72 is loaded; whereby the rotational center of the slavemedium 72 and the center position of the pattern 86 formed on thelower-side master medium 73 are matched. Then, the second base plate 77is lowered to insert the positioning pin 98 into the positioning hole 94a of the slave support axis 94, whereby the rotational center of theslave medium 72 and the center position of the pattern 86 formed on theupper-side master medium 73 supported in the master supporting member 9of the second base plate 77 are matched. Next, the upper and lowersurfaces of the slave medium 72 are conjoined with the respective databearing surfaces of the lower master medium 73and the upper mastermedium 74 at a predetermined pressure, and the transfer magnetic fieldis applied thereto to concurrently record the magnetic patterncorresponding to the transfer data borne on the respective mastermediums 73, 74 to the respective recording surfaces of the slave medium72.

The slave medium 72 is subjected to an initial magnetization process inadvance. This initial magnetization (direct current degaussing) consistsof generating a magnetic field of a magnetic field intensitydistribution having a magnetic field intensity portion of an intensityequal to or greater than that of the magnetic coercive force of theslave medium 72, on at least one or more positions of the trackdirection; wherein by rotating the slave medium 72 or the magnetic fieldin the track direction, the initial magnetization can be performed onall tracks. Further, it is more preferable that a magnetic field of amagnetic field intensity distribution having a magnetic field intensityportion equal to or greater than the magnetic coercive force of theslave medium 72 in only one direction at the position of the trackdirection, and a magnetic field intensity in the opposite direction lessthan the magnetic coercive force Hcs of the slave medium 72, is producedby generating a magnetic field of a magnetic field intensity at aportion of the track direction thereof; wherein by rotating the slavemedium 72 or the magnetic field in the track direction, the initialmagnetization can be performed on all tracks.

Further, the transfer magnetic field is applied in the track directionopposite that in which the initial magnetization magnetic field has beenapplied; there are no track directions in which the magnetic fieldintensity exceeds the maximum value of the optimal magnetic fieldintensity range (0.6-1.3 times the coercive magnetic force of the slavemedium 72), and a magnetic field intensity within the optimal magneticfield intensity range is present on at least one or more places in atleast one track direction. Further, the magnetic intensity in theopposite track direction is less than the optimal transfer magneticfield intensity in any track direction position across the entirerecording surface area of the slave medium 72.

According to the current embodiment, when the magnetic transfer is to beperformed: the center position of the pattern 86 formed on the mastermedium 73 is matched in advance with the center position of the slavesupport axis 94 and supported in said position-matched position; theslave medium 72 is conveyed onto said master medium 73; by matching thepositions of said slave medium 72 and said master medium 73, of whichthe position thereof has been matched and supported on the slave supportaxis 94, and then conjoining said master medium 73 and said slave medium72, the center position of the slave medium 72 and the center positionof the magnetic pattern 86 can be matched with a high degree ofaccuracy, whereby the positional accuracy obtained between the slavemedium 72 to which the transfer has been made and the rotational centerof the drive apparatus when said slave medium is loaded therein can beraised. Once a master medium 73 has been accurately positioned and fixedin place, a plurality of slave mediums 72 can be supplied to said mastermedium 73, wherein favorable magnetic transfers can be performedefficiently and successively, while the accuracy of the positioning isensured, whereby an improvement in productivity can be obtained.

Note that according to the current embodiment, the master supportingmember 95 is movable in the X and Y directions. However, for cases inwhich the master supporting member is a fixed position type supportingmember, the master medium 73 can be moved directly to match the positionthereof.

Hereinafter, still yet another embodiment of the present invention willbe explained. FIG. 19 is a cross-sectional view of the main portion of amagnetic transfer apparatus implementing the magnetic transfer methodaccording to an embodiment of the present invention. FIG. 20 is a planview of the pressure applying base according to the current embodiment.Note that each of said drawings is a model drawing, wherein thedimensions of the portions shown therein are different from the actualratios thereof.

According to the magnetic transfer apparatus 100 shown in FIG. 19, whichis an apparatus for performing single sided successive magnetictransfers, when a magnetic transfer is to be performed: the slavesurface (a magnetic recording surface) of a slave medium 102 (a magneticrecording medium), which has been subjected to an initial magnetizationprocess in advance, is brought into close contact with the data bearingsurface of a master medium 103, and conjoined therewith by a pressureapplying means 104 at a predetermined pressure to form a conjoined body;this conjoined body is then rotated by a rotating means 105; and amagnetic field applying means 106 applies a transfer magnetic field tosaid rotating conjoined body to transfer and record the servo patternsignal data borne on the data bearing surface of the master medium 103to the recording surface of the slave medium 102. According to thismagnetic transfer, when the conjoined body formed of the conjoinedmaster medium 103 and slave medium 102 is rotated by the rotationaldrive of the rotating means 105, the pressure applying means 104 appliespressure so as to not constrain the force component occurring in therotational direction.

The slave medium 102 is a disk shaped recording medium such as a harddisk, a flexible disk or the like, on which a magnetic recording layerhas been formed on both surfaces thereof. The slave medium 102 issubjected to an initial magnetization process in advance. This initialmagnetization (direct current degaussing) consists of generating amagnetic field of a magnetic field intensity distribution having amagnetic field intensity portion of an intensity equal to or greaterthan that of the magnetic coercive force Hcs of the slave medium 102, onat least one or more positions of the track direction; wherein byrotating the slave medium 102 or the magnetic field in the trackdirection, the initial magnetization can be performed on all tracks.Further, it is more preferable that a magnetic field of a magnetic fieldintensity distribution having a magnetic field intensity portion equalto or greater than the magnetic coercive force Hcs of the slave medium102 in only one direction at the position of the track direction, and amagnetic field intensity in the opposite direction less than themagnetic coercive force Hcs of the slave medium 102, is produced bygenerating a magnetic field of a magnetic field intensity at a portionof the track direction thereof; wherein by rotating the slave medium 102or the magnetic field in the track direction, the initial magnetizationcan be performed on all tracks.

The slave medium 102, disposed on the lower side as shown in FIG. 19, issupported on the upper surface of a discoid rotational base plate 151 ofa rotating means 105. A rotational axis 152 is provided on the center ofthe bottom surface of the rotational base plate 151, and the rotationaxis 152 is rotatably supported in a bearing member 153. Rotationalforce from a sprocket (not shown) in a drive motor is transferred tothis rotation axis 152 via a transfer member such as a timing belt, achain or the like, by a mechanism employing a rack and pinion gear orthe like, or directly from a motor, a rotary actuator (air or oilpressure), or the like; whereby the rotational base plate 151 is rotatedsubstantially one full rotation at a predetermined speed when themagnetic transfer is to be performed.

The master medium 103 is formed in a disk shape, and has a transfer databearing surface, which consists of a micro uneven pattern formed of apliable magnetic layer, on one surface thereof; this data bearingsurface is that which is to be conjoined with a recording surface of theslave medium 102. The surface of the master medium 103 opposite that ofthe data bearing surface is supported on the lower surface of the diskshaped pressing base plate 141 of the pressure applying means 104; thispressing base plate 141 presses the master medium 103 against the slavemedium 102.

A pressure applying base 142 is disposed on the upper portion of thepressing base plate 141. The pressing base plate 141 is supported onthis pressure applying base 142, and is movable in the contact andseparation directions relative to the rotational base plate 151, in thevertical direction. Further, a pressure transfer mechanism that does notconstrain the force component in the rotational direction between thepressure applying base 142 and the pressing base plate 141 is provided.

The pressure applying base 142 is provided with a circumferential wall142 b extending downward from the outer circumference of a round plateportion 142 a, and an engaging stopper portion 142 c is formed on thelower edge portion of this circumference wall 142 b as a portionprotruding into the interior thereof. A rod 142 d is attached to theupper portion of the pressure applying base 142, and is formed so as toconnect with a raising and lowering mechanism (not shown) so as tomovable up and down. A plurality of ball bearings 143 a, whichconstitutes a pressure transfer mechanism 143, is provided within thebottom surface of the pressure applying base 142. The pressing baseplate 141 is provided on the upper portion of the engaging stopperportion 142 c at the bottom surface of the round plate portion 142 a ofthe pressing base 142. The pressing base plate 141 is supported on theengaging stopper portion 142 c when the pressure applying base 142 israised, and moved as an integral unit therewith; when the pressureapplying base 142 is lowered so as to conjoin the master medium 103 andthe slave medium 102, the ball bearings 143 a pressure contact the uppersurface of the pressing base plate 141 to become thrust bearings andtransfer the pressure.

The pressure applying base 142 is fixed in the rotational direction, andthe rotation of the pressing base plate 141 and the rotational baseplate 151 as an integral unit is permitted by the rotation of the ballbearings 143 a. When pressure is applied, the pressing base plate 141 isprovided so as to be slightly movable up and down within the pressureapplying base 142, so that the engaging stopper portion 142 c isseparated from said pressing base plate 141.

As shown in FIG. 20, a depression portion 142 e is formed on the uppersurface of the pressing base plate 141 for insertion of the head portionof a magnetic field applying means 106; said magnetic head is configuredso as to approach the contact surfaces of the master medium 103 and theslave medium 102 and apply a transfer magnetic field thereto. It ispreferable that the ball bearings 143 a are not disposed on the portionof the bottom surface of the corresponding to the depression portion 142e. The ball bearings 143 a are provided with springs, and it ispreferable that said ball bearings 142 a be provided so that all of saidball bearings 143 a thrust out and retract so as to contact the uppersurface of the pressing base plate 141 and press thereagainst with auniform force.

Further, the center positions of the rotational base plate 151 and thepressing base plate 141 are determined by a positioning mechanism 107provided in an area more outward than the master medium 103 and theslave medium 102. In the case of the apparatus shown in the drawing, aplurality of positioning pins 171 are provided upright on the rotationalbase plate 151, and positioning holes 172 are opened on the pressingbase plate 141; the positioning of the center positions of the mastermedium 103 and the slave medium 102 is carried out by coupling saidpositioning pins 171 and said positioning holes 172. Further, therotational force of the rotational base plate 151 is transferred throughthis positioning mechanism 107 to the pressing base plate 141. Therotational force is transferred by the conjoinment force of the mastermedium 103 and the slave medium 102. The distal ends of the positioningpins 171 are provided in a tapered form; whereby the coupling thereofwith the positioning hole is facilitated.

The magnetic field applying apparatus 106 for applying the transfermagnetic field comprises: an electromagnetic apparatus provided with acore around which a coil has been wound and having a head portionextending in the radial direction of the conjoined master medium 103 andslave medium 102, which are supported in the rotational base plate 151and the pressing base plate 141; or a permanent magnet apparatusdisposed on one or both sides of the conjoined body. The magnetic fieldapplying apparatus 106 applies a transfer magnetic field directionparallel to the track direction, and in the direction substantially theopposite of that in which the initial magnetization magnetic field wasapplied. Note that the magnetic field applying apparatus 106 is providedat a position wherein it does not interfere with the pressure applyingbase 142 when it is raised or lowered.

The transfer magnetic field is applied so that there are no magneticfield intensities exceeding the maximum value of the optimal magneticfield intensity range (0.6-1.3 times the coercive magnetic force of theslave medium 102) in any track direction, and a magnetic field intensitywithin the optimal magnetic field intensity range is present on at leastone or more places in one track direction. Further, the magneticintensity in the opposite track direction is less than the optimaltransfer magnetic field intensity in any track direction position acrossthe entire recording surface area of the slave medium 102.

According to the magnetic transfer performed by the magnetic transferapparatus 100 comprises the steps of: first, raising the pressing baseplate 141, on which the master medium 103 has been positioned and fixedin said position, together with the pressure applying base 142; andpositioning the center position of the slave medium 102 on the uppersurface of the rotation base plate 151 and fixing the slave medium 102in said position, while in the state in which sufficient space has beenopened between the rotation base plate 151 and the slave medium 102 tofacilitate the removal and loading operations thereof. Next, thepressure applying base 142 is lowered, and while the positions of therotation base plate 151 and the pressing base plate 141 are beingmatched by use of the positioning mechanism 107, the transfer databearing surface of the master medium 103 is conjoined with the recordingsurface of the slave medium 102 at a predetermined pressure providedthrough the pressure transfer mechanism 143. Continuing, the drive motoris activated and the drive axis 152 is driven, whereby the rotationalbase plate 151 and the pressing base plate 141, which are connectedthrough the positioning mechanism 107, are rotated as an integral unit;at the same time, the transfer magnetic field is being applied to therotating conjoined body, whereby the transfer data such as a servosignal or the like formed on the transfer data bearing surface of themaster medium 103 is magnetically transferred and recorded onto therecording surface of the slave medium 102.

According to the current embodiment, the pressing base plate 141 of thepressure applying means 104, by the action of the pressure transfermechanism 143 constructed by the ball bearings 143 a, does not constrainthe force component occurring in the rotational direction when theconjoined body is being rotated and the transfer magnetic field isapplied, and the pressing base plate 141 rotates around the rotationalcenter of the rotational base plate 151, independently of the pressureapplying base 142, while applying the pressure. In this manner, no driveload due to the rotation is applied to the pressure applying base 142,and the slave medium 102 and the master medium 103 are rotated as anintegral unit wherein no slippage occurs therebetween; whereby amagnetic transfer with a high degree of accuracy can be performed.

FIG. 21 is a cross-sectional view of the main part of a magnetictransfer apparatus 100 provided with a pressure transfer mechanism 144according to another embodiment of the present invention.

According to the current embodiment, the pressure transfer mechanism 144is formed by an air gap. The pressing base plate 141 is structured inthe same manner as described above, and is supported between the roundplate portion 142 a of the pressure applying base 142 and the engagingstopper 142 c. A plurality of air expelling pores 144 a is opened on thebottom surface of the round plate portion 142 a of the pressure applyingbase 142. An air channel 144 b that passes through to the air expellingpores 144 a is provided through the interior of the round panel portion142 a; this air channel leads to the exterior portion and connects to apressurizing source (not shown), and supplies compressed air.

When the pressing base plate 141 has been lowered during application ofpressure, said pressing base plate 141 is separated from the pressureapplying base 142 by the air expelled from the air expelling pores 144 aof said pressure applying base 142, which is expelled toward the uppersurface of the pressing base plate 141, and the pressure is transferredin the state in which an air gap has been formed between the pressureapplying base 142 and the pressing base plate 141. The rotation of thepressing base plate 141 and the rotational base plate 151 as an integralunit, which is independent in relation to the pressure applying base142, is permitted by the non-contact sliding mobility provided by theair gap. Otherwise, the components are the same as those shown in FIG.19, and the magnetic transfer is performed in the same manner asoccurred in the embodiment shown therein.

According to the current embodiment as well, the pressing base plate 141of the pressure applying means 104, by the action of the pressuretransfer mechanism 144 constructed by the air gap formed by theexpulsion of the pressurized air, does not constrain the rotationalforce component in relation to the pressure applying base 142 when theconjoined body is being rotated and the transfer magnetic field applied,and the pressing base plate 141 rotates around the rotational center ofthe rotational base plate 151, independently of the pressure applyingbase 142, while applying the pressure. In this manner, no drive load dueto the rotation is applied to the pressure applying base 142, and theslave medium 102 and the master medium 103 are rotated as an integralunit wherein no slippage occurs therebetween; whereby a magnetictransfer with a high degree of accuracy can be performed.

Next, FIG. 22 is a drawing of a pressing base plate 141 and a rotationalbase plate 151 having a positioning mechanism 108 for positioning themaster medium 103 and the slave medium 102 according to anotherembodiment of the present invention, and FIG. 23 is a plan view of themaster medium 103 according to this embodiment.

The basic configuration of the pressing base plate 141 and therotational base plate 151 according to the current embodiment is thesame as that shown in FIG. 19. The master medium 103 supported in thepressing base plate 141 is formed so as to have a larger outer diameterthan that of the slave medium 102 supported in the rotational base plate151, and a positioning mechanism 108 for positioning the rotational baseplate 151 and the master medium 103 is disposed on the portion of saidmaster medium 103 which is outside of the portion thereof that conjoinswith the slave medium 102.

Four positioning pins 181 are erected on the rotational base plate 151that positions and supports the slave medium 102, and four positioningholes 182 (refer to FIG. 23) are provided on the master medium 103; thepositioning pins 181 and the positioning holes 182 constitute thepositioning mechanism 108. The distal ends of the positioning pins 181are provided in a tapered form, and the coupling thereof into thepositioning holes 182 is facilitated thereby.

According to the current embodiment, when the conjoining operation is tobe performed, the positioning pins 181 of the rotational base plate 151are inserted into the positioning holes 182 of the master medium 103,whereby the position of the rotational base plate 151, that is, of theslave medium 102 is matched to the position of the master medium 103. Inthis manner, the complicated positioning operation of matching theposition of the pressing base plate 141 and the position of the mastermedium 103 by use of the positioning mechanism 107 shown in FIG. 19becomes unnecessary, whereby simplification of the positioning operationcan be obtained without a loss in the accuracy thereof.

FIG. 24 is a drawing of a pressing base plate 141 and a rotational baseplate 151 having a positioning mechanism 109 according to yet anotherembodiment of the present invention. The basic configuration of thepressing base plate 141 and the rotational base plate 151 according tothe current embodiment is the same as that shown in FIG. 19. Apositioning mechanism 109 for positioning the rotational base plate 151and the master medium 103 is provided at the center portion of therotational base plate 151. A large diameter positioning pin 191 isprovided upright at the center portion of the rotational base plate 151,and a positioning hole 192 I provided at the center portion of themaster medium 103; the positioning pin 191 and the positioning hole 192constitute the positioning deice 109. The positioning pin 191 passesthrough the central aperture of the slave medium 102 and protrudestherefrom. The distal end of the positioning pin 191 is provided in atapered form, and the coupling thereof into the positioning hole 192 isfacilitated thereby. Note that the positioning of the slave medium 102can also be performed by the insertion of the positioning pin 191 of therotational base plate 151 through the central aperture 102 a of saidslave medium 102.

According to the current embodiment, when the pressure applyingoperation is to be performed, the positioning pin 191 of the rotationalbase plate 151 is inserted into the positioning hole 192 of the mastermedium 103, whereby the position of the rotational base plate 151, thatis, of the slave medium 102 is matched to the position of the mastermedium 103. In this manner, the complicated operation of matching theposition of the pressing base plate 141 with the position of the mastermedium 103 becomes unnecessary, in the same manner as shown in FIG. 22,whereby simplification of the positioning operation can be obtainedwithout a loss in the accuracy thereof. Further, if the positioning ofthe slave medium 102 is performed by use of the positioning pin 191, thepositioning operation can be further simplified.

Note that in the reverse to the above-described embodiment, the mastermedium 103 can be supported in the rotational base plate 151 and theslave medium 102 can be supported in the pressing base plate 141. Thefixation of the slave medium 102 and the master medium 103 in thepressing base plate 141 and the rotational base plate 151, respectively,can be performed by adsorption by air suction, for which a suctionchannel is formed. Further, it is preferable that small pores are openedon the portion of the master medium 103 other than that on which thetransfer pattern has been formed, so that the air on the contact portionof the slave medium 102 can be suctioned off therethrough, whereby noair remains between the contact surfaces.

Further, as in each of the embodiments described above, there are casesin which one recording surface of a slave medium 102 is conjoined withthe data bearing surface of a master medium 103 and a single sidedsuccessive magnetic transfer is performed on one side of the slavemedium 103, and cases in which both recording surfaces of the slavemedium 102 are conjoined with the respective data bearing faces of twomaster mediums and a double sided concurrent magnetic transfer isperformed on both recording surfaces of the slave medium 102. For casesin which the single sided successive magnetic transfer is performed, theslave medium 102 (or the master medium 103) is supported in therotational base plate 151 and the master medium 103 (or the slave medium102) is supported in the pressing base plate 141, said master medium 103and said slave medium 102 are conjoined and a transfer magnetic field isapplied thereto. After the single sided successive magnetic transfer hasbeen performed, the opposite surface of the slave medium 102 isconjoined with a master medium 103 on which an opposite surface patternhas been formed, and the transfer magnetic field is applied thereto. Forcases in which the double sided concurrent magnetic transfer isperformed, a first master medium 103 is supported in the rotational baseplate 151 and a second master medium 103 is supported in the pressingbase plate 141, the slave medium 102 is supported sandwiched betweenboth of the master mediums 103, 103, and both surfaces of the slavemedium 102 are conjoined with the respective surfaces of the mastermediums 103, 103, and the transfer magnetic field is applied thereto.

Basically, the magnetic transfer according to the present inventioncomprises the steps of: performing an initial magnetization of the slavemedium 102 in advance by applying a direct current magnetic field in onedirection of the track direction thereof; then, conjoining the slavesurface (a magnetic recording surface) of the slave medium 102 with thedata bearing surface of the master medium 103, which consists of apliable magnetic layer coated onto the micro uneven pattern formed onthe substrate thereof; and applying a transfer magnetic field in thetrack direction substantially the opposite of that in which the initialmagnetization has been performed, to perform the magnetic transfer. Asthe result, the magnetic pattern corresponding to the contact protrusionportions and the space of the depression portions of the pattern formedby the pliable magnetic layer of the data bearing face of the mastermedium 103 is transferred and recorded onto the slave surface (thetrack) of the slave medium 102.

1. A magnetic transfer apparatus comprising: a master fixing base forpositioning and supporting a master medium bearing a data signal, and aconjoining apparatus for bringing a slave medium that is to receive thetransfer of the data signal from the master medium into a state of closecontact to with the master medium to form a conjoined body, wherein saidmaster medium is exchanged as a whole along with the master fixing base.2. A magnetic transfer apparatus as defined in claim 1, furthercomprising a plurality of the master fixing bases, and a conveyor forsequentially conveying the master fixing bases to the transfer position.3. A magnetic transfer apparatus as defined in claim 1, furthercomprising a cleaning means for cleaning dust and debris attached to thesurface of a master medium supported in a master fixing base.